Therapeutic system

ABSTRACT

A therapeutic system comprising a therapeutic applicator for treating living tissues and an observation unit for determining the position of the applicator. The therapeutic energy applied from the applicator to the living tissues is controlled in accordance with data representing the position of the applicator, determined by the observation unit. It is therefore easy to operate the system even if the applicator and the observation unit (e.g., an MRI apparatus) are used at the same time. The image of the living tissues remains clear during the use of the therapeutic applicator.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a therapeutic system comprisinga medical applicator to be inserted into a living body and anobservation means such as an MRI (Magnetic Resonance Imaging) apparatus.

[0002] Generally, a therapeutic system comprises a medical applicatorsuch as a high-frequency instrument and an observation means such as anMRI apparatus. Before the medical applicator is inserted into a patient,the affected tissue within the patient, to which the applicator shouldbe guided, is detected by the observation means. The medical applicatoris inserted into the patient and guided to the affected tissue. Theapplicator is operated, thereby effectively performing high-frequencytreatment on the affected tissue.

[0003] In the conventional medical system, the applicator and theobservation means are driven independently of each other. To drive theapplicator and the observation means at the same time, they must besimultaneously controlled, while being observed. Simultaneous control ofthe medical applicator and the observation means is troublesome.

[0004] To make matters worse, the noise in the electromagnetic wavesemitted from the applicator may distort the image generated by theobservation means (e.g., MRI device). The image of the affected tissuemay be also distorted to become unclear, while high-frequency waves areapplied to the affected tissue.

BRIEF SUMMARY OF THE INVENTION

[0005] The present invention has been made in view of the foregoing. Itsobject is to provide a therapeutic system in which the medicalapplicator and the observation means (e.g., MRI apparatus) can be easilyoperated at the same time and in which the image generated by theobservation means remains clear all the time the medical applicator isused.

[0006] To achieve the object, a therapeutic system according to theinvention comprises: a therapeutic applicator adapted to be insertedinto a body cavity, for applying therapeutic energy to treat livingtissues present in the body cavity; observation means for indicating aposition which the therapeutic applicator takes in the body cavity; andcontrol means for controlling the therapeutic energy applied from thetherapeutic applicator to the living tissues, on the basis of datarepresenting the position which the therapeutic applicator takes in thebody cavity.

[0007] During the therapy, the observation means indicates the positionthe therapeutic applicator takes in the body cavity. The control meanscontrols the therapeutic energy applied from the applicator to theliving tissues, in accordance with the data representing the position ofthe applicator.

[0008] Hence, it is easy to operate the system even if the applicatorand the observation unit (e.g., an MRI apparatus) are used at the sametime. The image of the living tissues remains clear during the use ofthe therapeutic applicator.

[0009] Additional objects and advantages of the invention will be setforth in the description which follows, and in part will be obvious fromthe description, or may be learned by practice of the invention. Theobjects and advantages of the invention may be realized and obtained bymeans of the instrumentalities and combinations particularly pointed outhereinafter.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0010] The accompanying drawings, which are incorporated in andconstitute a part of the specification, illustrate presently preferredembodiments of the invention, and together with the general descriptiongiven above and the detailed description of the preferred embodimentsgiven below, serve to explain the principles of the invention.

[0011]FIG. 1 is a schematic representation of a therapeutic system,which is the first embodiment of the present invention;

[0012]FIG. 2A is a partially sectional view of a patient, illustratinghow the medical apparatus is used to perform treatment on the patient;

[0013]FIG. 2B is a longitudinal sectional view of the microwaveapplicator incorporated in the first embodiment of the invention;

[0014]FIG. 3 is a diagrammatic view showing the connection of thecontrol unit to some other components of the first embodiment;

[0015]FIG. 4 is a block diagram of the control section incorporated inthe first embodiment;

[0016]FIG. 5 is a flow chart explaining the operation of the firstembodiment of the invention;

[0017]FIG. 6 is a longitudinal sectional view of the patient, showingthe applicator of the first embodiment, which is inserted into theperitoneal cavity of the patient;

[0018]FIG. 7 is a longitudinal sectional view of the patient, showing anMR image of the region of the affected tissue, which is being coagulatedby the microwave applicator of the first embodiment;

[0019]FIG. 8 is a diagram illustrating the range of magneticsusceptibility for the main body of the microwave applicator, and alsothe range of magnetic susceptibility for the MR marker formed in themain body;

[0020]FIG. 9 is a longitudinal sectional view of the distal portion ofthe microwave applicator provided in a therapeutic system, which is thesecond embodiment of the present invention;

[0021]FIG. 10 is a longitudinal sectional view of the patient, showingthe applicator of the second embodiment, which is inserted into theperitoneal cavity of the patient;

[0022]FIG. 11 is a longitudinal sectional view of the patient, showingan MR image of the region of the affected tissue, which is beingcoagulated by the microwave applicator of the second embodiment;

[0023]FIG. 12 is a longitudinal sectional view of the distal portion ofthe microwave applicator provided in a therapeutic system, which is thethird embodiment of the present invention;

[0024]FIG. 13 is a longitudinal sectional view of the microwaveapplicator incorporated in a therapeutic system, which is the fourthembodiment of this invention;

[0025]FIG. 14 is a perspective view showing the insertion section of anendoscope and a applicator incorporated in a therapeutic systemaccording to the a fifth embodiment of the invention;

[0026]FIG. 15 is a perspective view of the applicator incorporated inthe fifth embodiment;

[0027]FIG. 16 is a longitudinal sectional view of the applicatorprovided in a therapeutic system according to the sixth embodiment ofthe invention;

[0028]FIG. 17 is a longitudinal sectional view of the applicatorincorporated in a therapeutic system according to the seventh embodimentof the invention;

[0029]FIG. 18 is a diagrammatic view showing the connection of thecontrol unit to some other components of a therapeutic system accordingto the eighth embodiment of the present invention;

[0030]FIG. 19 is a block diagram of the control section incorporated inthe eighth embodiment;

[0031]FIG. 20 is a flow chart explaining the operation of the eighthembodiment of the invention;

[0032]FIG. 21 is a schematic representation of a therapeutic system,which is the ninth embodiment of the present invention;

[0033]FIG. 22 is a flow chart explaining the operation of the ninthembodiment shown in FIG. 21;

[0034]FIG. 23 is a block diagram schematically showing a therapeuticsystem, which is the tenth embodiment of the invention;

[0035]FIG. 24 is a block diagram depicting the connection of the controlunit to some other components of the tenth embodiment;

[0036]FIG. 25 is a schematic representation of a therapeutic systemaccording to the eleventh embodiment of the present invention;

[0037]FIG. 26 is a block diagram illustrating the connection of thecontrol unit to some other components of the eleventh embodiment;

[0038]FIG. 27 is a schematic representation of a therapeutic systemaccording to the twelfth embodiment of the this invention;

[0039]FIG. 28 is a block diagram illustrating the connection of thecontrol unit to some other components of the twelfth embodiment;

[0040]FIG. 29 is a flow chart explaining the operation of the twelfthembodiment shown in FIG. 27;

[0041]FIG. 30 is a block diagram schematically showing a therapeuticsystem according to the thirteenth embodiment of the invention;

[0042]FIG. 31 is a perspective view of a therapeutic system, which isthe fourteenth embodiment of the present invention;

[0043]FIG. 32 is a graph representing the operating characteristic ofthe coaxial filter used in the fourteenth embodiment;

[0044]FIG. 33 is a diagram showing an MR tomogram generated in thefourteenth embodiment;

[0045]FIG. 34A is a graph illustrating the operation characteristic ofthe coaxial filter used in a therapeutic system according to thefifteenth embodiment of the invention;

[0046]FIG. 34B is a graph representing the operation characteristic ofthe coaxial filter used in a therapeutic system according to thesixteenth embodiment of this invention;

[0047]FIG. 35 is a perspective view of a therapeutic system, which isthe seventeenth embodiment of the present invention;

[0048]FIG. 36 is a graph representing the operation characteristic ofthe filter used in a therapeutic system according to the seventeenthembodiment of this invention;

[0049]FIG. 37A is a graph depicting the operation characteristic of thefilter used in a therapeutic system according to the eighteenthembodiment of the invention;

[0050]FIG. 37B is a graph representing the operation characteristic ofthe filter used in a therapeutic system according to the nineteenthembodiment of the present invention;

[0051]FIG. 38 is a schematic representation of a therapeutic systemaccording to the twentieth embodiment of the present invention;

[0052]FIG. 39 is a diagram schematically showing a therapeutic systemaccording to the twenty-first embodiment of this invention;

[0053]FIG. 40 is a diagram schematically showing a therapeutic systemaccording to the twenty-second embodiment of the present invention;

[0054]FIG. 41 is a diagram showing the coaxial filters incorporated in atherapeutic system according to the twenty-third embodiment of thepresent invention;

[0055]FIG. 42 is a diagram showing the filter incorporated in atherapeutic system according to the twenty-fourth embodiment of theinvention;

[0056]FIG. 43 is a schematic representation of a therapeutic systemaccording to the twenty-fifth embodiment of the present invention;

[0057]FIG. 44 shows an MR image generated in the twenty-fifth embodimentshown in FIG. 43;

[0058]FIG. 45 is a diagram showing the luminances detected at variouspoints in the MR image shown in FIG. 44;

[0059]FIG. 46 is a block diagram depicting the observation unit that isincorporated in the twenty-fifth embodiment;

[0060]FIG. 47 is a flow chart explaining the operation of thetwenty-fifth embodiment;

[0061]FIG. 48 is a flow chart explaining the operation of a therapeuticsystem according to the twenty-sixth embodiment of the invention;

[0062]FIG. 49 is a block diagram of the observation unit incorporated ina therapeutic system according to the twenty-seventh embodiment of thepresent invention;

[0063]FIG. 50 is a flow chart explaining the operation of the systemshown in FIG. 49;

[0064]FIG. 51 is a flow chart explaining the operation of a therapeuticsystem according to the twenty-eighth embodiment of the invention;

[0065]FIG. 52 is a flow chart explaining the operation of a therapeuticsystem according to the twenty-ninth embodiment of this invention;

[0066]FIG. 53 is a diagram illustrating the image displayed by thedisplay provided in the observation unit incorporated in a therapeuticsystem according to the thirtieth embodiment of the present invention;

[0067]FIG. 54 is a block diagram depicting the observation unit providedin the thirtieth embodiment;

[0068]FIG. 55 is a flow chart explaining the operation of the thirtiethembodiment;

[0069]FIG. 56 is a block diagram of the observation unit incorporated ina therapeutic system according to the thirty-first embodiment of thepresent invention;

[0070]FIG. 57 is a flow chart explaining the operation of thethirty-first embodiment;

[0071]FIG. 58 is a block diagram of the observation unit incorporated ina therapeutic system according to the thirty-second embodiment of thepresent invention;

[0072]FIG. 59 is a flow chart explaining the operation of thethirty-second embodiment;

[0073]FIG. 60 is a block diagram of the observation unit incorporated ina therapeutic system according to the thirty-third embodiment of thepresent invention;

[0074]FIG. 61 is a flow chart explaining the operation of thethirty-third embodiment;

[0075]FIG. 62 is a diagram showing a part of the image displayed by thedisplay provided in the observation unit incorporated in thethirty-third embodiment;

[0076]FIG. 63 is a graph illustrating how luminance changes along thereference line set in an MR image generated in the thirty-thirdembodiment;

[0077]FIG. 64 is a block diagram showing the observation unit providedin a therapeutic system according to the thirty-four embodiment of thepresent invention;

[0078]FIG. 65 is a flow chart explaining the operation of thethirty-fourth embodiment;

[0079]FIG. 66 is a diagram showing an MR image displayed by the displaysection incorporated in the observation unit of the thirty-fourthembodiment;

[0080]FIG. 67 is a schematic representation of a therapeutic systemaccording to the thirty-fifth embodiment of the present invention;

[0081]FIG. 68 is a block diagram depicting the observation unit providedin the thirty-fifth embodiment; and

[0082]FIG. 69 is a flow chart explaining the operation of thethirty-fifth embodiment.

DETAILED DESCRIPTION OF THE INVENTION

[0083] The first embodiment of the present invention will be describedwith reference to FIGS. 1 to 8. FIG. 1 shows the first embodiment, whichis a therapeutic system 1. The therapeutic system 1 comprises amicrowave therapeutic apparatus 2 and an MRI apparatus (observationmeans) 3. The microwave therapeutic apparatus 2 is designed to applytherapeutic energy to a subject to heal an affected tissue existing inthe living body. The MRI apparatus 3 is designed to show MR (MagneticResonance) images to a doctor.

[0084] The MRI apparatus 3 has an MR gantry 5 installed in an MRinspection room 4. The MR gantry 5 is provided to support a patient H.The MR gantry 5 is connected to an MRI apparatus control section 6located outside the MR inspection room 4.

[0085] A first monitor 7 is provided inside the MR inspection room 4 andconnected to the MRI control section 6, for displaying MR images of thepatient H lying on the MR gantry 5 during the MR inspection. A light 8is mounted on a stand protruding upwardly from the gantry 5. A scopeholder 10 is secured to one side of the gantry 5. The holder 10 holds anendoscope 8 (either a laparoscope 9 or an ultrasonic endoscope). Theendoscope 8 is connected to a light-source device 11 and a videoprocessor 12, both located outside the MR inspection room 4.

[0086] A second monitor 13 is provided in the MR inspection room 4. Thesecond monitor 13 is connected to the video processor 12. To perform MRinspection on the patient H, the illumination light is applied from thelight-source device 11 though the endoscope 9 into the peritoneal cavityof the patient H, which contains an affected tissue. The light reflectedfrom everything in the peritoneal cavity is applied to the endoscope 9.The endoscope 9 forms an image of the peritoneal cavity. The videoprocessor 12 converts the image into a video signal, which is suppliedto the second monitor 13 provided in the MR inspection room 4. Thesecond monitor 13 displays the image of the peritoneal cavity.

[0087] The therapeutic system has a pneumoperitoneal device 14. Thepneumoperitoneal device 14 is driven when the endoscope 9 is used. Thedevice 14 supplies gas into the peritoneal cavity of the patient H inorder to accomplish pneumoperitoneum.

[0088] The microwave therapeutic apparatus 2 comprises a microwaveapplicator (medical applicator) 15. The microwave applicator 15 isconnected by a microwave relay cable 16 with a microwave oscillator 17,which is located in the MR inspection room 4. A foot switch 18, anindicator lamp 19 and a speaker 20 are connected to the microwaveoscillator 17, which is provided in the MR inspection room 4.

[0089] The therapeutic system further comprises a control unit (controlmans) 21 for controlling the microwave therapeutic apparatus 2. Thecontrol unit 21 is arranged outside the MR inspection room 4. Themicrowave oscillator 17 and MRI apparatus control section 6, bothlocated outside the room 4, are connected to the control unit 21. Thefoot switch 18, indicator lamp 19 and speaker 20, all located in theroom 4, are also connected to the control unit 21.

[0090] The microwave applicator 15 has a rod-shaped main body 22 that isshown in FIG. 2B. The man body 22 comprises a conductor 23, an insulator24, and a distal conductor 25. The outer conductor 23 and the insulator24 are hollow cylinders, whereas the distal conductor 25 is a solidcylinder. The conductors 23 and 25 and the insulator 24 havesubstantially the same diameter. They are connected together in axialalignment, with the insulator 24 interposed between the conductors 23and 25. The microwave applicator 15 has an MW (Microwave) antenna, thecenter part of which is arranged in the insulator 24.

[0091] An inner conductor 26, which is a thin rod, extends through theouter conductor 23 and the insulator 24 in axial alignment therewith.The distal part of the inner conductor 26 is inserted into the axialhole made in the distal conductor 25. The distal conductor 25 has aradial hole 25 a that communicates with the axial hole. The radial hole25 a is filled with solder, which functions as an MR marker 27 to beused in magnetic resonance imaging (MRI). The solder holds the distalpart of the inner conductor 26 firmly and steadily in the axial hole ofthe distal conductor 25, while electrically connecting the innerconductor 26 to the distal conductor 25. The annular space defined bythe outer conductor 23, insulator 24 and inner conductor 26 is filledwith a dielectric body 28.

[0092] A distal tip 29 is set in screw engagement with the distalconductor 25. The distal end of the tip 29 is shaped like a corn,forming a sharp piercing part 29 a.

[0093] The main body 22 of the microwave applicator 15 has its outercircumferential surface covered with a transparent layer 30 made offluororesin. A resin cylinder 31, which serves as a grip, is mounted onthe proximal end portion of the main body 22. The outer circumferentialsurface of the resin cylinder 31 is covered with a resin coating 32.

[0094] A coaxial connector 33 is coupled to the proximal end of the mainbody 22. The microwave relay cable 16 can be connected to the coaxialconnector 33 as is shown in FIG. 2A.

[0095] The outer conductor 23, distal conductor 25 and inner conductor26 are made of material, such as Cu, which has magnetic susceptibilityranging from −10⁻³ to +10⁻³, as is shown in FIG. 8. The solder, whichforms the MR marker 27, has magnetic susceptibility of −10⁻⁵ or less, or+10⁻⁵ or more. Thus, the main body 22 of the applicator 15 has an MRmarker 27, which has magnetic susceptibility greater in absolute valuethan the magnetic susceptibility of the material of the main body 22.

[0096] Before therapy is performed on the patient H by means of thetherapeutic system 1, trocars 34 a and 34 b are set in the abdominalwall Ha of the patient H as is illustrated in FIG. 2A. The endoscope 9is inserted through the trocar 34 a into the peritoneal cavity Hb of thepatient H. The microwave applicator 15 is inserted through the trocar 34b into the peritoneal cavity Hb. An air-supplying tube 35 is connectedto the trocar 34 a. An ultrasonic probe 36 is placed on the abdomen ofthe patient H to apply ultrasonic waves into the peritoneal cavity Hb.

[0097] As shown in FIG. 3, the control unit 21 has a unit case 37 and anoperation panel 38. The operation panel 38 is provided on the unit case37. Various switches are arranged on the operation panel 38. They are astart switch 39, a stop switch 40, a high output switch 41, a low outputswitch 42, an MRI start switch 43, a high output display 44, a lowoutput display 45, high-output setting switches 46 a and 46 b, andlow-output setting switches 47 a and 47 b.

[0098] As shown in FIG. 4, the control unit 21 comprises a controlsection 48, an output switching section 49, a high-output settingsection 50, and a low-output setting section 51. The high-output settingsection 50 and the low-output setting sections 51 are connected to theoutput switching section 49. The high-output setting switches 46 a and46 b are connected to the high-output setting section 50. The low-outputsetting switches 47 a and 47 b are connected to the low-output settingsections 51.

[0099] The high output switch 41 and low output switch 42 are connectedto the output switching section 49. The start switch 39, stop switch 40,MRI start switch 43, high output display 44 and low output display 45are connected to the control section 48.

[0100] The operation of the therapeutic system 1 will be described.First, the patient H is laid on the MR gantry 5 provided in the MRinspection room 4, as is illustrated in FIG. 1. Then, as shown in FIG.2A, trocars 34 a and 34 b are set in the abdominal wall Ha of thepatient H. The insertion section of the endoscope 9 is inserted into theperitoneal cavity Hb of the patient H through the trocar 34 a, and themicrowave applicator 15 is inserted into the peritoneal cavity Hbthrough the trocar 34 b. If necessary, the ultrasonic probe 36 is placedon the abdomen of the patient H.

[0101] Illumination light is applied from the light-source device 11through the endoscope 9 to, for example, the affected tissue presents inthe peritoneal cavity Hb of the patient H. The endoscope 9 forms animage of the peritoneal cavity Hb. The video processor 12 converts theimage into a video signal. The video signal is supplied to the secondmonitor 13 provided in the MR inspection room 4. The second monitor 13displays the endoscopic image of the peritoneal cavity Hb.

[0102] During MR inspection, the first monitor 7 provided in the MRinspection room 4 displays an MR image of the patient H lying on the MRgantry 5. The first monitor 7 displays the image of the microwaveapplicator 15, too, as shown in FIGS. 6 and 7. In FIGS. 6 and 7, Hcindicates the liver of the patient, 52 denotes the artifact resultingfrom the MR marker 27, and 53 designates the region coagulated when themicrowave applicator 15 applies microwaves to the affected tissue.

[0103] In the present embodiment, the control unit 21 is operated,setting the output of the microwave applicator 15, before the microwaveapplicator 15 is used. The output of the microwave applicator 15 can beset at two values, i.e., high and low. The high output is set when thehigh-output setting switches 46 a and 46 b are pushed. The low output isset when the low-output setting switches 47 a and 47 b are pushed. Thehigh output is selected when the high output switch 41 is pushed, andthe low output is selected when the low output switch 42 is pushed.Alternatively, the high output and the low output may be switched fromone to the other, every time an output-changeover switch (not shown) ispushed.

[0104] After the output has been set for the microwave applicator 15,the start switch 39 of the control unit 21 is depressed. Then, thecontrol unit 21 transmits an output start signal to the microwavetherapeutic apparatus 2. At the same time, the control unit 21 transmitsa control signal to the microwave therapeutic apparatus 2. The controlsignal corresponds to the output value set in the control unit 21. Uponreceipt of the output start signal, the microwave therapeutic apparatus2 starts operating, whereby the microwave applicator 15 appliesmicrowaves to the affected tissue present in the peritoneal cavity Hb.Thus, microwave therapy is started.

[0105] During the microwave therapy, the control unit 21 transmits acontrol signal to the microwave therapeutic apparatus 2, controlling theoutput of the apparatus 2. At the same time, the control unit 21transmits an MRI start signal to the MRI apparatus 3. In response to theMRI start signal, the MRI apparatus 3 starts generating an MR image ofthe patient H. The output signal from the MRI apparatus control section6 is input to the control section 48 of the control unit 21, whereby theMRI apparatus 3 provides an MR image that indicates the position of themicrowave applicator 15.

[0106] The data representing the position of the microwave applicator 15is supplied to the control unit 21. In accordance with this data thecontrol unit 21 controls the output of the microwave applicator 15,i.e., the therapeutic energy to be applied from the applicator 15 to theaffected tissue existing in the peritoneal cavity Hb.

[0107] How the control unit 21 controls the microwave applicator 15 willbe explained, with reference to the flow chart of FIG. 5.

[0108] First, it is determined in Step S1 whether the stop switch 40 hasbeen pushed or not. If NO in Step S1, the operation goes to Step S2. InStep S2, it is determined whether the high output switch 41 and lowoutput switch 42 of the output-switching section 49 have been depressedor not. If it is determined that neither the switch 41 nor the switch 42has been depressed, the operation goes to Step S3.

[0109] In Step S3, it is determined whether the MRI start switch 43 hasbeen depressed or not. If NO in Step S3, the operation goes to Step S4.

[0110] In Step S4, it is determined whether the setting switches (i.e.,high-output setting switches 46 a and 46 b and low-output settingswitches 47 a and 47 b) have been pushed or not. If YES in Step S4, theoperation goes to Step S5. In Step S5, the various values set arechanged. The operation then returns to Step S1. If NO in Step S4, thevalues set are not changed, and the operation returns to Step S1.

[0111] If YES in Step S2, that is, if the output switch 41 or the outputswitch 42, or both switches 41 and 42 have been pushed, the operationgoes to Step S6. In Step S6, it is determined whether the microwaveoutput of the microwave oscillator 17 is high or not. If YES in Step S6,the operation goes to Step S7.

[0112] In Step S7, the microwave output of the microwave oscillator 17is changed to low. Then, in Step S8, the control unit 21 transmits anMRI start signal to the MRI apparatus 3. Thus, the microwave therapeuticapparatus 2 is controlled such that the output of the oscillator 17, ifhigh, is changed to low when the MRI start switch 43 is pushed while themicrowave applicator 15 is applying microwaves to the affected tissue.The control unit 21 then transmits an MRI start signal to the MRIapparatus 3.

[0113] After the control unit 21 transmits an MRI start signal to theMRI apparatus 3 in Step S8, the operation goes to Step S9. In Step S9 itis determined whether or not the control unit 21 has received an MRI endsignal from the MRI apparatus 3. Step S9 is repeated until it isdetermined that the unit 21 has received an MRI end signal. If YES inStep S9, the operation returns to Step S1. Hence, after the completionof the MR imaging, the output of the microwave oscillator 17 remains notchanged to high until the control unit 21 receives an MRI end signalfrom the MRI apparatus 3.

[0114] If NO in Step S6, that is, if the microwave output of themicrowave oscillator 17 is not high, the operation goes to Step S10. InStep S10 the microwave output of the microwave oscillator 17 is changedto high. The operation then returns to Step S1.

[0115] When the stop switch 40 is pushed while the microwave therapeuticapparatus 2 is operating, it is determined in Step S1 that the stopswitch 40 has been depressed. In this case, the operation goes to StepS11. In Step S11, the control unit 21 transmits an output stop signal tothe microwave therapeutic apparatus 2. In response to the output stopsignal, the apparatus 2 stops operating. As a result, the microwaveapplicator 15 ceases to apply microwaves to the affected tissue existingin the peritoneal cavity Hb. The microwave therapy is therebyterminated.

[0116] If NO in Step S1, that is, if it is determined that the stopswitch 40 has not been pushed, either the high output switch 41 or theoutput-changeover switch (not shown) may be depressed after the MRimaging has completed. In this case, the microwave therapeutic apparatus2 is controlled to change the output of the microwave oscillator 17 tohigh.

[0117] The low output switch 42 may be pushed while the output of themicrowave oscillator 17 remains high, thus changing the output of theoscillator 17 to low. Alternatively, the stop switch 40 may be pushedwhile the output of the microwave oscillator 17 remains high, therebycausing the oscillator 17 to stop generating microwaves. In either case,the control unit 21 transmits an MRI start signal to the MRI apparatus3.

[0118] The therapeutic system 1 described above, i.e., the firstembodiment of the invention, is advantageous in the following respects.

[0119] When the microwave therapeutic apparatus 2 and the MRI apparatus3 are used simultaneously, the output of the microwave applicator 15,i.e., the energy applied to the affected tissue, is automaticallydecreased. The noise in the electromagnetic waves applied from theapplicator 15 imposes on the MRI image generated by the MRI apparatus 3can therefore be minimized. The MRI image of the peritoneal cavity Hb,showing the affected tissue, is sufficiently clear even while themicrowave therapeutic apparatus 2 is being used. Further, therefore maybe also distorted to become unclear, while high-frequency waves areapplied to the affected tissue. Since the MRI image is not blurred,showing the affected tissue somewhat larger than it is, there is nopossibility that microwaves are applied to anything existing around theaffected tissue.

[0120] In the first embodiment, the microwave therapeutic apparatus 2can continuously perform microwave therapy, while the MR imaging isbeing effected. It is therefore possible to prevent the temperature ofthe living tissue from falling during the MR imaging. This helps toaccomplish effective therapy.

[0121] Further, it is easy to operate the microwave therapeuticapparatus 2 and the MRI apparatus 3 at the same time. This is becausethe control unit 21 automatically decreases the output of the microwaveapplicator 15 (i.e., the energy applied to the affected tissue) whilethe MRI apparatus 3 is performing MR imaging.

[0122] Still further, the main body 22 of the microwave applicator 15 iselectrically insulated reliably and is biologically adapted, because theouter surface of the main body 22 is covered with a transparent layer 30made of fluororesin. In addition, no living tissues will stick to themain body 22 of the applicator 15 when the microwave applicator 15 isused to cauterize the affected tissue.

[0123] In the first embodiment, the solder, forming the MR marker 27,electrically connects the distal part of the inner conductor 26 to thedistal conductor 25. Hence, the artifact 52 resulting from the MR marker27 located before the center of the MW antenna of the applicator 15 canbe shown in the MR image as shown in FIG. 6. The artifact 52 thus shownserves to locate the center of the MW antenna, from which therapeuticenergy is emitted. This helps to enhance the operability of themicrowave applicator 15 and the safety and reliability of the microwavetherapy. Moreover, the microwave applicator 15 is easy to assemble sincethe MR marker 27 is located in front of the center part of the MW(Microwave) antenna, which is arranged in the insulator 24.

[0124] The MRI apparatus 3, which serves as means for determining theposition of the microwave applicator 15, may be replaced by anultrasonic imaging apparatus or an X-ray CT (Computed Tomography)apparatus. Furthermore, the microwave therapeutic apparatus 2, which isused as the therapeutic apparatus, may be replaced by a laser apparatus,a RF therapeutic apparatus, an HF therapeutic apparatus, or anultrasonic-wave apparatus. Moreover, a tissue-separating current may besupplied to the microwave applicator 15 for a short time when the stopswitch 40 is pushed at the end of the microwave therapy. Still further,a graduation may be printed on the microwave applicator 15 so that thedoctor may know how deep the applicator 15 has been inserted into theperitoneal cavity Hb, by reading the graduation shown in the RM image ofthe patient H.

[0125] The therapeutic system 1, which is the first embodiment of theinvention, comprises a therapeutic applicator for applying therapy to aliving tissue and an observation means for determining the position ofthe applicator. The energy applied from the applicator to the livingtissue is controlled in accordance with the data representing theposition of the applicator. Hence, it is easy to operate the therapeuticapplicator and the observation means, such as an MRI apparatus, at thesame time. Further, the observation means provides a clear MR image ofthe patient while the therapeutic applicator is being used.

[0126] FIGS. 9 to 11 show the second embodiment of the presentinvention. The second embodiment is identical to the first embodiment(FIGS. 1 to 8), except for the structure of the microwave applicator 15.

[0127] As shown in FIG. 9, the microwave applicator 15 has two MRmarkers 27 and 61. The first MR marker 27 of the same type as the oneused in the first embodiment is arranged at a position which is distalto the center part of the MW antenna (i.e., the center part of theinsulator 24) of the applicator 15. The second MR marker 61, which ismade of solder, is arranged at a position, which is proximal to thecenter part of the MW antenna.

[0128] The distance La between the first MR marker 27 and the centerpart of the MW antenna, and the distance L2 between the second MR marker61 and the center part of the MW antenna have relation of La>Lb, La<Lb,or La=Lb. The second MR marker 61 may be made of material other thansolder, such as one having magnetic susceptibility of −10⁻³ or less, or+10⁻³ or more.

[0129] The microwave applicator 15 has its center of energy-emission atthe center part of the MW antenna, which lies between the first MRmarker 27 and the second MR marker 61. Therefore, two artifacts 52 and62 will appear in an MR image that has been generated by the MRIapparatus 3, as is illustrated in FIG. 10.

[0130] The second embodiment is advantageous in some respects. As shownin FIG. 11, neither the artifact 52 nor the artifact 62 conceals theimage of an affected tissue that is treated with microwave (i.e.,coagulated region 53). This is because the center of energy-emission(i.e., center part of the MW antenna) is located between the first MRmarker 27 and second MR marker 61, both made of solder and resulting inthe first artifact 52 and second artifact 62, respectively. As a result,how the living tissue is coagulated can be clearly observed. Thisenables the doctor to know how the living tissue changes, from thebeginning of the microwave therapy he or she is performing by the use ofthe microwave applicator 15. The safety of the microwave therapy cantherefore be enhanced.

[0131]FIG. 12 shows the microwave applicator 15 incorporated in atherapeutic system according to the third embodiment of the invention.The third embodiment differs from the first embodiment (FIGS. 1 to 8) inthe structure of the microwave applicator 15. As FIG. 12 shows, thedistal conductor 25 has an axial hole 71 made in its proximal end part.The hole 71 communicates with the interior of the outer conductor 23,which is a hollow cylinder. The distal end part of the dielectric body28 is inserted in the axial hole 71.

[0132] The distal end part of the dielectric body 28, which is insertedin the axial hole 71 renders the distal conductor 25 more rigid than inthe case where only the distal part of the inner conductor 26 supportsthe distal conductor 25 as in the first embodiment. Ultimately, thedielectric body 28 serves to strengthen the junction between the distalconductor 25 and the insulator 24, which are relatively fragile.

[0133]FIG. 13 shows the microwave applicator 15 incorporated in atherapeutic system, which is the fourth embodiment of the invention. Thefourth embodiment differs from the first embodiment (FIGS. 1 to 8) inthe structure of the microwave applicator 15. As FIG. 13 shows, themicrowave applicator 15 has a distal conductor 81, instead of the distalconductor 25 and the distal tip 29. Further, a titanium coating 82,instead of the transparent layer 30 made of fluororesin, covers thedistal conductor 81 and the outer conductor 23.

[0134] An insulating sheath 83 is mounted on the proximal part of thedistal conductor 81, the insulator 24, and the distal part of the outerconductor 23. An insulating cover 84 is mounted on the outercircumferential surface of the coaxial connector 33.

[0135] The titanium coating 82 can be thinner than the fluoreresin layer30 to have the same strength. Hence, the main body 22 of the microwaveapplicator 15 can have a smaller outer diameter than its counterpart ofthe first embodiment. In addition, MR markers can be made of thetitanium coating 83 covering the distal conductor 81 and the outerconductor 23.

[0136]FIGS. 14 and 15 depict the flexible applicator 91 incorporated ina therapeutic system, which is the fifth embodiment of the presentinvention. The flexible applicator 91 is designed for accomplishingtherapy on affected tissues in the esophageal veins, the bile duct, orthe like.

[0137] As shown in FIG. 14, the flexible applicator 91 has an elongatedinsertion section 94. The insertion section 94 comprises a flexiblecoaxial cable 95, an MW antenna 96, and an insulating sheath 97. Theinsertion section 94 is guided into a body cavity through the instrumentchannel 93 of an MR-compatible endoscope (or an MR endoscope) 92. Theflexible coaxial cable 95 is provided in the insertion section 94 andcomprises an inner conductor and an outer conductor surrounding theinner conductor. The MW antenna 96, which applies therapeutic energy, isconnected to the distal end of the coaxial cable 95. The insulatingsheath 97 covers the flexible coaxial cable 95 and the MW antenna 96.

[0138] The MW antenna 96 comprises a distal conductor 98, a proximalconductor 99, and a dielectric body 100. The distal conductor 98 isconnected to the inner conductor of the coaxial cable 95. The proximalconductor 99 is connected to the outer conductor of the coaxial cable95. The dielectric body 100 is interposed between the distal conductor98 and the proximal conductor 99.

[0139] An MR marker 101 is provided on the distal part of the flexiblecoaxial cable 95, at a position proximal to the MW antenna 96. A sheath102 made of fluororesin is mounted on the entire insertion section 94 ofthe flexible applicator 91.

[0140] To use the flexible applicator 91, the insertion section of theMR-compatible endoscope 92 is inserted into a tubular cavity, e.g., theesophagus Hd, of the patient. The distal end of the insertion section isguided to the vicinity of the affected tissue, e.g., phlebeurysm He,existing in the esophagus Hd. Then, the insertion section 94 of theflexible applicator 91 is inserted into the esophagus Hd through theinstrument channel 93 of the MR-compatible endoscope 92. The doctor canset the MW antenna 96 at a desired position with respect to the surfaceof the esophagus Hd, referring to the position of the MR marker 101 onthe flexible applicator 91. Once set so, the MW antenna 96 can coagulateor cauterize the phlebeurysm He efficiently.

[0141] The fifth embodiment described above is advantageous in that theMW antenna 96, i.e., the means for emitting therapeutic energy, can beeasily located. This is because the ring-shaped MR marker 101 isprovided on the distal part of the insertion section 92 of the flexibleapplicator 91, at a position proximal to the MW antenna 96. The doctorcan therefore correctly place the MW antenna 96 at a desired positionwith respect to the surface of the tubular cavity. Once set so, the MWantenna 96 can coagulate or cauterize the affected tissue present in thetubular cavity. Thus, the operability of the microwave applicator 15 andthe safety and reliability of the microwave therapy can be enhanced. Asa result, even if either coagulation or necrosis is induced in the thinwall of a tubular organ, necrosis or deciduation of the tissue willoccur, and no pits will be formed in the wall of the tubular organ.

[0142]FIG. 16 shows the flexible applicator 91 incorporated in atherapeutic system, which is the sixth embodiment of the presentinvention. The flexible applicator 91 differs from its counterpart ofthe fifth embodiment, as will be described below.

[0143] In the fifth embodiment, one the ring-shaped MR marker 101 isprovided on the distal part of the insertion section 94 of the flexibleapplicator 91, at a position proximal to the MW antenna 96. In the sixthembodiment, a second MR marker 103 is arranged at the rear of thering-shaped MR marker 101. The dielectric body 100 is the middle part ofthe MW antenna 96 that applies microwave to coagulate or cauterize theaffected tissue in the wall of the tubular organ. The distance Labetween the body 100 and the front MR marker 101 is equal to thedistance Lb between the front MR marker 101 and the second MR marker103. While the flexible applicator 91 is being used, the position of thedielectric body 100 can be inferred from the distance Lb between the MRmarker 101 and 103.

[0144] In the sixth embodiment, the second MR marker 103 is located atthe back of the MR marker 101 which is identical to its counter part ofthe fifth embodiment, and the distance La is equal to the distance Lb(La=Lb). Hence, it is easier for a doctor to locate the dielectric body100 that is the center of energy-emission.

[0145]FIG. 17 shows the monopolar paracentetic applicator 111incorporated in a therapeutic system that is the seventh embodiment ofthe invention.

[0146] The mono-polar paracentetic applicator 111 is used in combinationwith an electrode provided outside the patient. The applicator 111 has aneedle electrode 112 made of titanium. A connector 113 is mounted on thedistal part of the needle electrode 112. A connector housing 114 ismounted on the connector 113.

[0147] A needle 115 having a length La is attached to the distal end ofthe needle electrode 112. Two ring-shaped MR markers 116 and 117 areprovided on the distal part of the electrode 112, at the back of theneedle 115. The MR markers 116 and 117 are spaced apart by a distanceLc. The distance Lc is equal to the distance Lb between the tip of theneedle 115 and the front MR marker 116 (Lb=Lc). The needle electrode 112is covered with a fluororesin coating 118.

[0148] While the mono-polar paracentetic applicator 111 is being used,the position of the tip of the needle 115 attached to the distal end ofthe needle electrode 112 can be inferred from the distance Lc betweenthe MR markers 116 and 117. Further, the applicator 111 may have asmaller diameter, ultimately reducing the pain the patient may havewhile receiving the therapy. This is possible because the needle 115having an appropriate length La is attached to the distal end of theneedle electrode 112 made of titanium.

[0149] FIGS. 18 to 20 show a therapeutic system according to the eighthembodiment of the present invention. The eighth embodiment is identicalto the first embodiment (FIGS. 1 to 8), except for the structure of thecontrol unit 21.

[0150] As shown in FIG. 18, some additional switches and displays areprovided on the operation panel 38 of the control unit 21. Theadditional switches are: an automatic/manual switch 121, high-outputperiod setting switches 123 a and 123 b, low-output period settingswitches 125 a and 125 b, and total high-output period setting switches127 a and 127 b. The additional displays are a high-output perioddisplay 122, a low-output display 124, and a total high-output perioddisplay 126. The control unit 21 is set into automatic control mode ormanual control mode by operating the switch 121. Once set in the manualmode, the control unit 21 can operate in the same way as in the firstembodiment to perform various controls. Once set in the automaticcontrol mode, the control unit 21 can perform various controls inaccordance with the periods of time that have been set by operating theswitches 123 a, 123 b, 125 a, 125 b, 127 a and 127 b.

[0151] As shown in FIG. 19, the control section 48 that is provided inthe control unit 21 is connected to a time counting section 128. Thetime counting section 128 is connected to a high-output period settingsection 129 and a low-output period setting section 130.

[0152] How the control unit 21 controls the microwave applicator 15 inthe eighth embodiment will be explained.

[0153] First, the operation panel 38 of the control unit 21 is operated,setting conditions in which the applicator 15 of the microwavetherapeutic apparatus 2 should be operated. More specifically, thehigh-output period setting switches 123 a and 123 b are operated,setting a high-output period for which the applicator 15 is to applymicrowaves at high level. The high-output period display 122 displaysthe high-output period thus set. Similarly, the low-output periodsetting switches 125 a and 125 b are operated, setting a low-outputperiod for which the applicator 15 is to apply microwaves at low level.The low-output display 124 displays the low-output period thus set.Further, the total high-output period setting switches 127 a and 127 bare operated, setting a total high-output period for which theapplicator 15 is to apply microwaves at high level. The totalhigh-output period display 126 displays the total high-output period.

[0154] Next, the automatic/manual switch 121 is operated, whereby thecontrol unit 21 is set into either the automatic control mode or themanual control mode. If the control unit 2 is set into the manualcontrol mode, the high-output period, low-output period and totalhigh-output period set by operating the operation panel 38 will beinvalidated. In this case, the control unit 21 will operate in the sameway as in the first embodiment.

[0155] If the control unit 2 is set into the automatic control mode, thecontrol unit 21 will perform various controls in accordance with thevarious periods set by operating the operation panel 38, as will bedescribed with reference to the flow chart of FIG. 20.

[0156] First, the start switch 39 of the control unit 21 is depressed.The control unit 21 generates a signal representing the high-outputperiod. This signal is supplied to the microwave therapeutic apparatus2. The microwave applicator 15 of the therapeutic apparatus 2 startsemitting microwaves in Step S21. At the same time, the time countingsection 128 starts counting down the high-output period. Then, in StepS22, it is then determined whether the stop switch 40 has been pushed ornot.

[0157] If NO in Step S22, that is, if the stop switch 40 has not beenpushed, the operation goes to Step S23. In Step S23, it is determinedwhether the high-output period has elapsed or not. If NO in Step S23,the operation goes to Step S24, in which a total high-output period iscalculated. Then, in Step S25, it is determined whether the totalhigh-output period has elapsed or not. If NO in Step S25, it isdetermined in Step S26 whether any setting switches have been pushed ornot. If YES in Step S26, the operation goes to Step S27, in which thevarious values set are changed. The operation then returns to Step S22.If NO in Step S26, the operation returns directly to Step S22.

[0158] If YES in Step S23, that is, if it is determined that thehigh-output period has elapsed, the operation goes to Step S28. In StepS28, the low output is transmitted to the microwave therapeuticapparatus 2. The output of the apparatus 2 is thereby switched to thelow value. The microwave applicator 15 of the apparatus 2 startsemitting microwaves. At the same time, the time counting section 128starts counting down the low-output period.

[0159] Thereafter, in Step S29, the control unit 21 transmits an MRIstart signal to the MRI apparatus 3. Then, in Step S30, it is determinedwhether or not the control unit 21 has received an MRI end signal fromthe MRI apparatus 3. If NO, Step S30 is repeated until the high-outputperiod elapses. Upon lapse of the high-output period, the output of themicrowave therapeutic apparatus 2 is switched to the low value, and theMRI apparatus 3 starts MRI imaging.

[0160] If YES in Step S30, that is, if it is determined that the controlunit 21 has received an MRI end signal from the MRI apparatus 3, theoperation goes to Step S31. In Step S31, it is determined whether thelow-output period has elapsed or not. If NO, Step S31 is repeated. IfYES, the operation returns to Step S21. In Step S21, the output of themicrowave therapeutic apparatus 2 is switched to the high value again,only if the control unit 21 has received an MRI end signal.

[0161] The microwave applicator 15 emits high-output microwaves andlow-output microwaves alternately and repeatedly. The applicator 15stops emitting microwaves when the total high-output period set elapses.Then, the MRI apparatus 3 carries out MR imaging. Thereafter, themicrowave therapy is terminated.

[0162] If YES in Step S22, that is, if it is determined that the stopswitch 40 has been pushed in the course of the microwave therapy, thecontrol unit 21 transmits an output stop signal to the microwavetherapeutic apparatus 2. In response to the output stop signal, theoscillator 17 stops generating microwaves. As a result, the microwaveapplicator 15 ceases to apply microwaves in Step S32. Then, in Step S33,the control unit 21 transmits an MRI start signal to the MRI apparatus3, which performs MR imaging.

[0163] In the eighth embodiment, the various output periods set byoperating the operation panel 38 will be invalidated when theautomatic/manual switch 121 provided on the panel 38 of the control unit21 is operated, thereby setting the control unit 21 into the manualcontrol mode. In this case, the control unit 21 will operate in the sameway as in the first embodiment. Thus, the microwave output of themicrowave oscillator 15, i.e., the therapeutic energy applied to theliving tissue, is automatically decreased while both the microwavetherapeutic apparatus 2 and the MRI apparatus 3 are operating at thesame time, the latter performing MR imaging. The influence that thenoise in the microwaves applied from the applicator 15 imposes on theMRI apparatus 3 can therefore be minimized. As a result, the imageprovided by the MRI apparatus 3 is sufficiently clear even while themicrowave therapeutic apparatus 2 is being used.

[0164] Furthermore, once the control unit 21 has been set into theautomatic control mode by operating the automatic/manual switch 121, themicrowave applicator 15 automatically emit high-output microwaves andlow-output microwaves alternately and repeatedly, and the MRI apparatus3 automatically repeats the MR imaging. Hence, the eighth embodiment canachieve the same advantages as the first embodiment.

[0165] In the eighth embodiment, the MRI apparatus 3 may be replaced byan ultrasonic imaging apparatus or an X-ray CT apparatus. And themicrowave therapeutic apparatus 2 may be replaced by a laser apparatus,an RF therapeutic apparatus, an HF therapeutic apparatus, or anultrasonic-wave apparatus. Moreover, a tissue-separating current may besupplied to the microwave applicator 15 for a short time when the stopswitch 40 is pushed at the end of the microwave therapy. If such acurrent is so supplied to the microwave applicator 15, bleeding will beprevented at the living tissue when the applicator 15 (i.e., electrode)is pulled out of the tissue after the completion of the microwavetherapy.

[0166]FIGS. 21 and 22 show a therapeutic system according to the ninthembodiment of the invention. The ninth embodiment is identical to thefirst embodiment (FIGS. 1 to 8), except for the structure of the controlunit 21.

[0167] As shown in FIG. 21, the control unit 21 comprises an MR-imageprocessing section 141, a therapeutic device control section 142, and areference output section 143.

[0168] In the ninth embodiment, the MRI apparatus 3 repeats MR imagingat intervals, while the microwave applicator 15 is applying microwavesto an affected tissue. How this is performed will be explained below,with reference to the flow chart of FIG. 22.

[0169] First, the MRI apparatus 3 repeats MR imaging at certainintervals in Step S41. In Step S42, the previous MR image and the latestMR image are compared, finding a color difference d between the MRimages compared. An increase in the size of the treated region isdetermined from the color difference d.

[0170] Next, in Step S43, it is determined whether the color differenced obtained in Step S42 is equal to or greater than the minimum propercolor difference d1. If YES, that is, if d≧d1, the operation goes toStep S44. In Step S44, it is determined whether the color difference dis equal to or less than the maximum proper color difference d2. If YES,that is, if d≦d2, the operation returns to Step S41.

[0171] If the color difference d falls outside a prescribed range ofproper values, the output of the microwave applicator 15 is changed aswill be described below.

[0172] Namely, if NO in Step S43, that is, if d<d1, the therapy speed istoo low. In this case, the operation goes to Step S45, in which one ofthe following processes A to D is carried out.

[0173] A. To increase the output of the applicator 15

[0174] B. To lengthen the period of outputting microwaves

[0175] C. To increase the temperature set for the living tissue

[0176] D. To alter the output waveform to increase the therapy speed

[0177] If NO in Step S44, that is, if d>d2, the therapy speed is toohigh. In this case, the operation goes to Step S46, in which one of thefollowing processes A to D is carried out.

[0178] A. to decrease the output of the applicator 15

[0179] B. To shorten the period of outputting microwaves

[0180] C. To decrease the temperature set for the living tissue

[0181] D. To alter the output waveform to decrease the therapy speed

[0182] The ninth embodiment described above is advantageous in that thesafety and reliability of the microwave therapy can be enhanced. This isbecause the microwave therapeutic apparatus 2 is controlled to effectthe therapy at the best possible speed.

[0183] In the ninth embodiment, too, the MRI apparatus 3 may be replacedby an ultrasonic imaging apparatus or an X-ray CT apparatus. Further,the microwave therapeutic apparatus 2 may be replaced by a laserapparatus, an RF therapeutic apparatus, an HF therapeutic apparatus, oran ultrasonic-wave apparatus.

[0184]FIGS. 23 and 24 show a therapeutic system according to the tenthembodiment of the invention. The tenth embodiment is identical to thetherapeutic system 1 (FIGS. 1 to 8) that is the first embodiment, exceptfor the following respects.

[0185] As shown in FIG. 23, the microwave applicator 15 has two MRmarkers 151 and 152. As shown in FIG. 24, the control unit 21incorporates a control section 153, a marker detecting section 154, anda motion calculating section 155. The control section 153 is connectedto the microwave therapeutic apparatus 2. The marker detecting section154 is connected to the MRI apparatus control section 6 provided in theMRI apparatus 3. The motion calculating section 155 is connected to andlocated between the control section 153 and the marker detecting section154.

[0186] A reference-point setting section 156 is connected to the motioncalculating section 155. The section 156 is designed to set a referencepoint 157 at a given position on the MR screen of the first monitor 7.The first monitor 7 is provided to display an MR image generated by theMRI apparatus 3. More specifically, the first monitor 7 displays theimage of the organ Hf being treated and the image of the microwaveapplicator 15, as is illustrated in FIG. 23. A maximum-displacementsetting section 158 is connected to the control section 153.

[0187] The control section 153 provided in the control unit 21 monitorsthe positional relation of the two MR markers 151 and 512 and thereference point 157 in order to detects the displacement of themicrowave applicator 15. Upon detecting an excessive displacement of theapplicator 15 from the reference point 157, the control section 153causes the microwave oscillator 17 to stop generating microwaves.

[0188] The operation of the therapeutic system 1 according to the tenthembodiment will be explained.

[0189] At first, the doctor operates the maximum-displacement settingsection 158, thus setting the maximum displacement the applicator 15 mayhave with respect to the reference point 157 without causing troubles.Then, the doctor pierces the organ Hf with the microwave applicator 15.The MRI apparatus 3 generates MR images of the organ Hf and applicator15, which are displayed on the MR screen of the first monitor 7. Thedoctor operates the reference-point setting section 156, thereby settinga reference point 157 on the MR screen of the first monitor 7. The datarepresenting the positional relation the MR markers 151 and 152 on theapplicator 15 and the reference point 157 have at this time is stored,as an initial position value, into the memory (not shown) incorporatedin the control section 153.

[0190] Every time the MRI apparatus 3 generates an MR image of the organHf and applicator 15, the positional relation of the MR markers 151 and152 and the reference point 157 is detected. If the displacement of themicrowave applicator 15 exceeds the maximum value set by operating themaximum-displacement setting section 158, it is determined that theapplicator 15 has been displaced excessively. In this case, the controlsection 153 causes the microwave oscillator 17 to stop generatingmicrowaves.

[0191] Moreover, if neither the MR marker 151 nor the MR marker 512 isdisplayed on the MR screen of the first monitor 7, the section 153causes the microwave oscillator 17 to stop generating microwaves.

[0192] In the tenth embodiment, the microwave oscillator 17automatically stops generating microwaves when the microwave applicator15 is displaced excessively. That is, since the output of the microwavetherapeutic apparatus 2 is controlled in accordance with the positionalrelation of the images MR markers and reference point, all generated bythe MRI apparatus 3, the safety and reliability of the microwave therapycan be enhanced.

[0193] Also in the tenth embodiment, the MRI apparatus 3 may be replacedby an ultrasonic imaging apparatus or an X-ray CT apparatus. Further,the microwave therapeutic apparatus 2 may be replaced by a laserapparatus, an RF therapeutic apparatus, an HF therapeutic apparatus, oran ultrasonic-wave apparatus.

[0194]FIGS. 25 and 26 show a therapeutic system according to theeleventh embodiment of the present invention. The eleventh embodiment isidentical to the tenth embodiment (FIGS. 23 and 24), except for thestructure of the control unit 21.

[0195] As depicted in FIG. 26, a signal-value change calculating section161 is used in place of the motion calculating section 155. The section161 is connected to and arranged between the control section 153 and themarker detecting section 154.

[0196] Further, an initial signal-value outputting section 162 isconnected to the signal-value change calculating section 161. A maximumluminance-change setting section 163 is connected to the control section153. As in the tenth embodiment, the first monitor 7 displays the imageof the organ Hf being treated and the image of the microwave applicator15, as is illustrated in FIG. 25. In FIG. 25, Hg denotes a protectedregion of the organ Hf.

[0197] A monitor marker 164 can be displayed on the MR screen of thefirst monitor 7, for example in the protected region Hg of the organ Hfthat should be protected from any damage. The monitor marker 164 can bemoved to any desired position on the MR screen, by operating anappropriate input device such as a keyboard or a mouse.

[0198] The operation of the eleventh embodiment will be described.First, the doctor pierces the organ Hf with the microwave applicator 15.Then, the MRI apparatus 3 generates MR images of the organ Hf andapplicator 15, which are displayed on the MR screen of the first monitor7. The doctor moves the applicator 15, setting the monitor marker 164 inthe protected region Hg of the organ Hf displayed on the MR screen ofthe first monitor 7. Data representing the luminance of the image of theprotected region Hg designated by the monitor marker 164 is stored, asinitial value, into the memory (not shown) incorporated in the controlsection 153.

[0199] Further, the doctor operates the maximum luminance-change settingsection 163, setting a maximum luminance change. Every time the MRIapparatus 3 generates an MR image of the organ Hf and applicator 15after the microwave therapy has been started, the luminance of the imageof the protected region Hg is compared with the initial value stored inthe memory of the control section 153, thereby determining a change inluminance. If the luminance change exceeds the maximum luminance changeset by operating the maximum luminance-change setting section 163, it isdetermined that degeneration has occurred in the protected region Hg ofthe organ Hf. In this case, the control section 153 causes the microwaveoscillator 17 to stop generating microwaves.

[0200] As indicated above, the monitor marker 164 is set in any regionof the MR image of the organ Hf that should be protected from damage.When the luminance change in the region of the MR image exceeds thepreset maximum luminance change, it is determined that degeneration hasoccurred in this region. Then, the control section 153 causes themicrowave oscillator 17 to stop generating microwaves. Hence, theeleventh embodiment helps to enhance the safety and reliability of themicrowave therapy.

[0201] In the eleventh embodiment, too, the MRI apparatus 3 may bereplaced by an ultrasonic imaging apparatus or an X-ray CT apparatus.Further, the microwave therapeutic apparatus 2 may be replaced by alaser apparatus, an RF therapeutic apparatus, an HF therapeuticapparatus, or an ultrasonic-wave apparatus.

[0202] FIGS. 27 to 29 show a therapeutic system according to the twelfthembodiment of this invention. The twelfth embodiment is identical to thetherapeutic system 1 (FIGS. 23 and 24), i.e., the tenth embodiment,except for the following respects.

[0203] As shown in FIG. 28, the twelfth embodiment has an applicatormoving device 171, a distance calculating section 172, a therapy-point(target) setting section 173, and a maximum-distance setting section175. The applicator moving device 171 is provided outside the controlunit 21 and connected to the control section 153 of the control unit 21,for moving the microwave applicator 15 in the axial direction thereof.The distance calculating section 172, therapy-point setting section 173and maximum-distance setting section 175 are provided in the controlunit 21.

[0204] The distance calculating section 172 is connected to and locatedbetween the control section 153 and the marker detecting section 154.The therapy-point setting section 173 is connected to the distancecalculating section 172, for setting a plurality of therapy points 174on the MR screen of the first monitor 7 that displays an MR imagegenerated by the MRI apparatus 3. The therapy points 174 indicate thoseparts of the organ Hf that must be treated with microwaves. Theapplicator moving device 171 moves the microwave applicator 15 under thecontrol of the control section 153, until the MR marker 151 on theapplicator 15 to a therapy point 174. The applicator 15 then appliesmicrowaves to the parts of the organ Hf, i.e. the therapy points 174.The doctor operates the maximum-distance setting section 175, settingthe longest distance the MR marker 151 can be moved from one therapypoint 174 to another, without causing any trouble during the microwavetherapy.

[0205] The operation of the twelfth embodiment will be explained. First,the doctor pierces the organ Hf with the microwave applicator 15. TheMRI apparatus 3 generates MR images of the organ Hf and applicator 15,which are displayed on the MR screen of the first monitor 7. The doctoroperates the therapy-point setting section 173, setting therapy points174 on the MR screen of the first monitor 7.

[0206] Thereafter, the control section 153 controls the applicatormoving device 171, which moves the applicator 15 until the monitormarker 151 reaches the first therapy point 174. The applicator 15 isoperated, applying microwaves to that part of the organ Hf which islocated at the first therapy point 174. When the part of the organ Hf istreated thoroughly, the applicator 15 stops applying microwaves underthe control of the control section 153. The control section 153 controlsthe applicator moving device 171, which moves the microwave applicator15 in the axial direction thereof, so that the MR marker 151 may movesto the second therapy point 174.

[0207] How the microwave applicator 15 is moved, to move the MR marker151 from the first therapy point 174 to the second therapy point 171,will be described with reference to the flow chart of FIG. 29.

[0208] At first, in Step S61, the applicator moving device 171 moves themicrowave applicator 15 toward the second therapy point 174. In StepS62, the MRI apparatus 3 performs MR imaging, whereby an MR image isdisplayed on the MR screen of the first monitor 7.

[0209] Thereafter, in Step S63, the distance calculating section 172calculates the distance between the MR marker 151 and the second therapypoint 174. In Step S64, it is determined whether the distance calculatedin Step S63 is longer than the maximum distance set by operating themaximum-distance setting section 175. If NO, the operation returns toStep S61, and Steps 62 and 63 are repeated.

[0210] If YES in Step S64, that is, if the distance calculated in StepS63 is equal to or shorter than the maximum distance, it is determinedthat the MR marker 151 has moved to the second therapy point 174. Inthis case, the operation goes to Step S65. In Step S65, the control unit21 transmits an output start signal to the microwave therapeuticapparatus 2. In response to the output start signal, the applicator 15starts applying microwaves to that part of the organ Hf which is locatedat the second therapy point 174.

[0211] In Step S66, it is determined whether a prescribed period of timehas elapsed or not from the start of application of microwaves. If NO,the operation returns to Step S66. If YES, the operation goes to StepS67, in which the control unit 21 transmits an output stop signal to themicrowave therapeutic apparatus 2. In response to the output stopsignal, the applicator 15 stops applying microwaves.

[0212] Then, in Step S68 it is determined whether there is any therapypoint 174 to which microwaves have not been applied. If YES, theoperation returns to Step S61. Steps S61 to S68 are repeated until it isdetermined in Step S 68 that microwaves have been applied to all therapypoints 174 set by operating the therapy-point setting section 173. Then,the microwave applicator 15 is no longer moved in the organ Hf, becausethe microwave therapy has been performed at every therapy point 174 heor she had set by operating the therapy-point setting section 173.

[0213] As mentioned above, the twelfth embodiment has the applicatormoving device 171 for moving the applicator 15 in the axial directionthereof, and the therapy-point (target) setting section 173 for settingtherapy points 174 on the MR screen of the first monitor 7. The controlsection 153 controls the device 171 such that the MR marker 151 on theapplicator 15 moves from one therapy point 174 to the next one. Hence,the microwave therapeutic apparatus 2 can automatically effect microwavetherapy sequentially at all therapy points 174. Therefore, it is easy tooperate the microwave therapeutic apparatus 2 and the MRI apparatus 3 atthe same time in the therapeutic system according to the twelfthembodiment.

[0214] Also in the twelfth embodiment, the MRI apparatus 3 may bereplaced by an ultrasonic imaging apparatus or an X-ray CT apparatus.Further, the microwave therapeutic apparatus 2 may be replaced by alaser apparatus, an RF therapeutic apparatus, an HF therapeuticapparatus, or an ultrasonic-wave apparatus.

[0215]FIG. 30 shows a therapeutic system according to the thirteenthembodiment of the invention. The thirteenth embodiment is identical tothe therapeutic system 1 (FIGS. 23 and 24), i.e., the tenth embodiment,except for the following respects.

[0216] As illustrated in FIG. 30, a reference-point marker 181 is set onthe MR screen of the first monitor 7 that displays an MR image generatedby the MRI apparatus 3. The positional relation between thereference-point marker 181, on the one hand, and the MR markers 151 and152 on the microwave applicator 15, on the other hand, is detected everytime the MRI apparatus generates an MR image. If the distance betweeneach MR marker and the reference-point marker 181 is longer than apreset value, it is determined that the microwave applicator 15 has beenexcessively moved in the organ Hf being treated with microwaves. In so,the control unit 21 causes the microwave oscillator 17 to stopgenerating microwaves.

[0217] Neither the MR marker 151 nor the MR marker 152 may be displayedon the MR screen of the first monitor 7. In this case, the control unit21 causes the microwave oscillator 17 to stop generating microwaves.

[0218] In the thirteenth embodiment, the microwave oscillator 17automatically stops generating microwaves when the applicator 15 ismoved too much with respect to the reference-point marker 181. Hence,the safety and reliability of the microwave therapy can be enhanced,even if the patient H lying on the MR gantry 5 during the MR inspection.

[0219] FIGS. 31 to 33 show a therapeutic system, which is the fourteenthembodiment of the present invention. This embodiment is identical to thetherapeutic system 1 (FIGS. 1 to 8), i.e., the first embodiment, exceptfor the following respects.

[0220] The microwave oscillator 17, which is provided outside the MRinspection room 4 as shown in FIG. 31, incorporates a magnetron. Themagnetron is used as a microwave generator, for generatinghigh-frequency microwaves for therapeutic purpose. The magnetron isconnected to the microwave applicator 15 provided in the MR inspectionroom 4, by a microwave relay cable 16 that is a coaxial cable. A coaxialfilter 191 is provided on the microwave relay cable 16. Hence, thecoaxial filter 191 is arranged between the output section of themagnetron and the input section of the MR inspection room 4.

[0221] The coaxial filter 191 operates as a high-pass filter (HPF)having a threshold frequency fc. The threshold frequency fc is lowerthan the frequency f1 of the therapeutic microwaves and higher than theintermediate frequency f2 of the MRI waves, as is seen from FIG. 32.That is, f1>fc>f2. Thus, the coaxial filter 191 transmits thetherapeutic microwaves and attenuates the waves.

[0222] The MRI apparatus 3 is provided in the MR inspection room 4,though not shown in FIG. 31. The MRI apparatus 3 generates an MRtomogram of the illustrated in FIG. 33. The MR tomogram includes animage of the patient's liver Hc and a region 53 thereof, coagulated asthe microwave applicator 15 (not shown) applies microwaves in the leverHc.

[0223] As described above, the coaxial filter 191 is provided on themicrowave relay cable 16 that connects the microwave applicator 15 andthe magnetron which are provided in the MR inspection room 4 and themicrowave oscillator 17, respectively. The filter 191 can thereforeremove noise, if any, in the therapeutic microwaves before thesemicrowaves are transmitted into the MR inspection room 4, while notattenuating the therapeutic microwaves at all. The MRI tomogram is freefrom the influence of the noise in the therapeutic microwaves. Thismakes it possible to carry out microwave therapy and MR imaging at thesame time. Hence, there will arise no problem if a magnetron, which isan inexpensive component but generates noise over a broad band, is usedto generate therapeutic microwaves. In addition, the coaxial filter 191can be a simple filter such as a waveguide or the like.

[0224] A therapeutic system according to the fifteenth embodiment of thepresent invention will be described with reference to FIG. 34A. Thefifteenth embodiment differs from the fourteenth embodiment (FIGS. 31 to33), only in the operating characteristic of the coaxial filter 191. Thecoaxial filter 191 operates as a band-pass filter (BPF), not as ahigh-pass filter as in the fourteenth embodiment. As can be understoodfrom FIG. 34A, the coaxial filter 191 transmits therapeutic microwaveshaving frequency f1 and attenuates the MRI microwaves. The cut-offfrequency fc of the filter 191 has an upper-limit value fcH and alower-limit value fcL. These values fcH and fcL, the frequency f1 of thetherapeutic microwaves, and the intermediate frequency f2 of the MRIwaves have the relationship of: f1>fcH>fcL>f2.

[0225] In the fifteen embodiment, the coaxial filter 191 is a band-passfilter. Therefore, the microwave therapy and the MR imaging can beeffected at the same time by the use of a single filter, regardless ofthe intermediate frequency f2 of the MRI waves. Operating as a band-passfilter, the coaxial filter 191 transmits the therapeutic microwaves andattenuates the MRI waves as shown in FIG. 34A.

[0226] A therapeutic system according to the sixteenth embodiment of thepresent invention will be described with reference to FIG. 34B. Thesixteenth embodiment differs from the fourteenth embodiment (FIGS. 31 to33), only in the operating characteristic of the coaxial filter 191. Thecoaxial filter 191 operates as a band-cut filter (BCF), not as ahigh-pass filter as in the fourteenth embodiment, and attenuates onlythe MRI microwaves having frequency f2. The coaxial filter 191 has acut-off frequency having an upper-limit value fcH and a lower-limitvalue fcL. As can be seen from FIG. 34B, the values fcH and fcL, thefrequency f1 of the therapeutic microwaves, and the frequency f2 of theMRI waves have the relationship of: f1>fcH>f2>fcL.

[0227] Since the coaxial filter 191 is a band-cut filter (BCF), itattenuates only microwaves of a specific band. Hence, the filter 191generates heat only a little while operating and can be made small. Themicrowave therapy and the MR imaging can be performed at the same timeby the use of a single filter, regardless of the frequency f1 of thetherapeutic microwaves. The filter 191 may be replaced by a waveguidethat has been adjusted in size to have the cut-off frequency describedabove.

[0228]FIGS. 35 and 36 show a therapeutic system according to theseventeenth embodiment of the invention. The therapeutic system 1according to the seventeenth embodiment differs from the fourteenthembodiment (FIGS. 31 to 33) in the following respects.

[0229] As shown in FIG. 35, a high-frequency power supply 204 isprovided outside the MR inspection room 4, i.e. the magnetic shield roomfor use in MR imaging. The power supply 204 includes a high-frequencywave generator of two-wire output type (not shown), such as an electrodeknife apparatus. Two high-frequency wave relay cables 201 and 202 areconnected at one end to the high-frequency wave generator arranged inthe power supply 204. The first cable 201 is connected at the other endto an active electrode (not shown) provided in the MR inspection room 4.The second cable 202 is connected at the other end to a return electrode(not shown) provided in the MR inspection room 4. A two-wire filter 203is provided on the cables 201 and 202. The filter 203 operates as alow-pass filter (LPF) having a threshold frequency fc. The thresholdfrequency fc is lower than the frequency f1 of the therapeuticmicrowaves and higher than the frequency f2 of the MRI microwaves, as isseen from FIG. 36. That is, f1>fc>f2. Thus, the coaxial filter 191transmits the MRI microwaves and attenuates the therapeutic microwaves.

[0230] As described above, the cables 201 and 202 connects the two-wirehigh-frequency wave generator provided in the power supply 204 to theactive electrode and return electrode, both provided in the MRinspection room 4. Since the two-wire filter 203 is provided on thecables 201 and 202, can remove noise, if any, in the MRI waves beforethe MRI microwaves are transmitted from the power supply 204 to the MRinspection room 4, while attenuating the therapeutic microwaves. The MRItomogram is therefore free from the influence of the noise in the MRIwaves. This makes it possible to carry out microwave therapy and MRimaging at the same time.

[0231] A therapeutic system according to the eighteenth embodiment ofthe invention will be described with reference to FIG. 37A. Theeighteenth embodiment differs from the seventeenth embodiment (FIGS. 35and 36), only in the operating characteristic of the two-wire filter203. In the eighteenth embodiment, the two-wire filter 203 provided onthe cables 201 and 202 operates as a band-pass filter (BPF), not as alow-pass filter as in the seventeenth embodiment. As can be understoodfrom FIG. 37A, the filter 203 transmits the MRI microwaves havingfrequency f2 and attenuates the therapeutic microwaves havingfrequencies similar to frequency f1.

[0232] Thanks to the use of a single filter, i.e., the two-wire filter203 functioning as a band-pass filter, the microwave therapy and the MRimaging can be performed at the same time, regardless of the frequencyf2 of the MRI waves.

[0233] A therapeutic system according to the nineteenth embodiment ofthis invention will be described with reference to FIG. 37B. Thenineteenth embodiment differs from the seventeenth embodiment (FIGS. 35and 36), only in the operating characteristic of the two-wire filter203. In the nineteenth embodiment, the two-wire filter 203 provided onthe cables 201 and 202 operates as a band-cut filter (BCF), not as alow-pass filter as in the seventeenth embodiment. As can be understoodfrom FIG. 37B, the filter 203 attenuates only the therapeutic microwaveshaving frequency f1.

[0234] Thanks to the use of a single filter, i.e., the two-wire filter203 functioning as a band-cut filter, the microwave therapy and the MRimaging can be performed at the same time, regardless of the frequencyf1 of the therapeutic microwaves. The two-wire filter 203 can removenoise, if any, in therapeutic microwaves which have harmonic componentssuch as pulse-shaped components.

[0235]FIG. 38 shows a therapeutic system according to the twentiethembodiment of the present invention. This system comprises a microwaveapplicator 15, a diagnostic ultrasonic probe 212, a coaxial cable 213, amicrowave generator 214, and an ultrasonic imaging apparatus 215. Themicrowave applicator 15 is used as a therapeutic applicator for applyingtherapeutic energy to an affected tissue. The diagnostic ultrasonicprobe 212 is connected to the microwave applicator 15 and serves asobservation means for detecting the position of the microwave applicator15. The coaxial cable 213 connects the applicator 15 to the microwavegenerator 214. The diagnostic ultrasonic probe 212 is connected to theultrasonic-wave imaging apparatus 215.

[0236] The system further comprises a coaxial filter 216, which isprovided on the coaxial cable 213. The coaxial filter 216 operates as ahigh-pass filter. Its threshold frequency is lower than the intermediatefrequency of the therapeutic microwaves and higher than the ultrasonicwaves used in the ultrasonic imaging apparatus 215.

[0237] In the twentieth embodiment, the coaxial filter 216, whichoperates as a high-pass filter, is provided on the coaxial cable 213which connects the microwave applicator 15 to the microwave generator214. The filter 216 therefore removes noise which may adverselyinfluence the ultrasonic imaging performed by the ultrasonic imagingapparatus 215, without attenuating the therapeutic microwaves suppliedfrom the microwave generator 214 to the microwave applicator 15. Hence,the ultrasonic imaging apparatus 215 can generate a clear ultrasonicimage even if the ultrasonic imaging and the microwave therapy arecarried out at the same time, by means of the probe 212 and theapplicator 15, respectively.

[0238] The coaxial filter 216 may be replaced by a band-pass filter thathas the operating characteristic shown in FIG. 34A, or by a band-cutfilter that has the operating characteristic shown in FIG. 34B.

[0239]FIG. 39 shows a therapeutic system, which is the twenty-firstembodiment of the present invention. This therapeutic system comprises adiagnostic ultrasonic probe 212, an ultrasonic imaging apparatus 215, aresectoscope 221, and a two-wire high-frequency wave generator 224. Theresectoscope 221 is used as a therapeutic applicator for applyingtherapeutic energy to an affected tissue. The diagnostic ultrasonicprobe 212 is similar to its counterpart of the twentieth embodiment(FIG. 38).

[0240] The resectoscope has a slender insertion section 222, which canbe inserted into a body cavity of a patient. The insertion section 222contains a loop electrode 223. A high-frequency output is supplied tothe loop electrode 223 from the two-wire high-frequency wave generator224.

[0241] Two cables 225 and 226 are connected at one end to thehigh-frequency wave generator 224. The loop electrode 223 provided inthe resectoscope 221 is connected to the cable 225. The high-frequencygenerator 224 incorporates a return electrode (not shown), which isconnected to the cable 226.

[0242] A two-wire filter 227 is provided on the cables 225 and 226,which supply the therapeutic energy to the resectoscope 221 from thetwo-wire high-frequency wave generator 224. The filter 227 operates as alow-pass filter having a threshold frequency that is lower than thefrequency of the therapeutic high-frequency waves and higher than thefrequency of the ultrasonic imaging waves.

[0243] To perform ultrasonic imaging and high-frequency wave therapy,the diagnostic ultrasonic probe 212 and the insertion section 222 of theresectoscope 221 are inserted into, for example, the rectum Hh andurethra Hi of the patient, respectively, as is illustrated in FIG. 39.

[0244] As indicated above, the two-wire filter 227 functioning as alow-pass filter is provided on the two cables 225 and 226 that supplythe therapeutic energy from the generator 224 to the resectoscope 221.Hence, the filter 227 can remove noise in the therapeutic high-frequencywaves, without attenuating the therapeutic waves similar to sine waves,before the loop electrode 223 approaches the diagnostic ultrasonic probe212. As a result, the ultrasonic imaging apparatus 215 can generate aclear ultrasonic image even if the ultrasonic imaging and thehigh-frequency wave therapy are carried out at the same time, by meansof the probe 212 and the applicator 15, respectively.

[0245] The twenty-first embodiment is not limited to a system, wherein aresectoscope is employed as therapeutic applicator. Rather, it may beapplied to a system in which any other therapeutic applicator thatapplies high-frequency energy to accomplish therapy, while an ultrasonicimaging apparatus is operating.

[0246]FIG. 40 shows a therapeutic system according to the twenty-secondembodiment of this invention. The twenty-second embodiment is differentfrom the twenty-first embodiment (FIG. 39) in two respects only. First,a paracentetic bipolar electrode 231 is used in place of theresectoscope 221. Secondly, an ultrasonic probe 212 for use incombination with a raparoscope. The twenty-second embodiment can achievethe same advantage as the twenty-first embodiment.

[0247] A therapeutic system according to the twenty-third embodiment ofthe invention will be described, with reference to FIG. 41. Thetwenty-third embodiment differs from the fourteenth embodiment (FIGS. 31to 33) in the following respects.

[0248] A terminal board 242 is fitted in a sidewall of the MR inspectionroom 4, i.e. the magnetic shield room for use in MR imaging, and acoaxial noise filter 243 is mounted on the terminal board 242. Thecoaxial nose filter 243 is provided on a microwave relay cable 16 (i.e.,a coaxial cable), which connects the microwave applicator 15 and themicrowave generator (e.g., magnetron) which are provided in the MRinspection room 4 and the microwave oscillator 17, respectively. Thefilter 243 is either a band-pass filter or a high-pass filter, whichtransmits the MRI waves used in the MRI apparatus 3 to generate MRimages.

[0249] As described above, the noise filter 243 is provided on themicrowave relay cable 16. Therefore, the microwave therapy and the MRIimaging can be carried out at the same time, irrespective of thefrequency of the microwaves generated by the microwave generator.

[0250] A therapeutic system, which is the twenty-fourth embodiment ofthe invention, will be described with reference to FIG. 42. Thetherapeutic applicator used in this embodiment is a resectoscope 221having a loop electrode 223, as in the twenty-first embodiment (FIG.39). And a diagnostic ultrasonic probe 212 is used as observation meansfor detecting the position of the resectoscope 221.

[0251] In the twenty-fourth embodiment, a terminal board 242 is fittedin a side wall of the MR inspection room 4 (i.e. the magnetic shieldroom for use in MR imaging), as in the twenty-third embodiment (FIG.41). A two-wire noise filter 251 is mounted on the terminal board 242.The filter 251 is provided on two cables 225 and 226 for supplyingtherapeutic energy from a high-frequency generator 224, as in thetwenty-first embodiment (FIG. 39). The filter 251 is either a band-passfilter or a high-pass filter, which transmits the MRI waves used in theMRI apparatus 3 to generate MR images.

[0252] As described above, the noise filter 251 is provided on the twocables 225 and 226. Therefore, the microwave therapy and the MRI imagingcan be carried out at the same time, irrespective of the frequency ofthe output frequency of the high-frequency generator 224.

[0253] FIGS. 43 to 47 show a therapeutic system 261, which is thetwenty-fifth embodiment of the present invention. FIG. 43 schematicallydepicts this therapeutic system 261. As shown in FIG. 43, the system 261comprises an MRI apparatus 262 and a therapeutic apparatus 263. The MRIapparatus 262 comprises an MRI gantry 264 and an MRI controller 265,which are connected by an MRI signal cable 266. The therapeuticapparatus 263 comprises a therapeutic energy generator 268 and atherapeutic probe 270 (see FIG. 44). The therapeutic probe 270 isconnected to the therapeutic energy generator 268 by a cable 269.

[0254] The MRI apparatus 262 further comprises an observation unit 271,which is provided between the MRI controller 265 and the therapeuticenergy generator 268. The observation unit 271 is connected to the MRIcontroller 265 by a signal cable 272 and to the therapeutic energygenerator 268 by a signal cable 273. In the therapeutic system 261,adoctor operates the therapeutic apparatus 263, performing therapy, whileobserving the MRI image generated by the MRI apparatus 262.

[0255] As shown in FIG. 46, the MRI controller 265 comprises an MRIcontrol section 274 and an image signal output section 275. The input ofthe MRI control section 274 is connected to the MRI gantry 264 by theMRI signal cable 266. The output of the MRI control section 274 isconnected to the image signal output section 275.

[0256] As FIG. 46 shows, the therapeutic energy generator 268 comprisesa therapeutic energy control section 276, a therapeutic energygenerating section 277, and a signal input/output section 278. Thetherapeutic energy generating section 277 is connected to thetherapeutic probe 270 by the cable 269.

[0257] The observation unit 271 comprises a control section 279, asignal input/output section 280, an image signal input unit 281, adisplay section 282, a measuring-points setting section 283, a referenceluminance setting means 284 and an indicator means 285. The signalinput/output section 280, image signal input unit 281, display section282, measuring-points setting section 283, reference luminance settingmeans 284 and indicator means 285 are connected to the control section279. The image signal input unit 281 is connected to the image signaloutput section 275 of the MRI controller 265 by the signal cable 272.The signal input section /output section 280 is connected to the signalinput/output section 278 of the therapeutic energy generator 268 by thesignal cable 273. The display section 282 incorporates a monitor 267 fordisplaying an MR image.

[0258] The measuring-points setting section 283 is connected to an inputdevice (not shown) such as a keyboard, a mouse, a track ball, a touchpen, or the like. As the input device is operated, the section 283 setsfour measuring points (a) to (d) in the MR image generated by the MRIapparatus 262, around the image Hj of the affected region as isillustrated in FIG. 44. Luminance is measured at the measuring points(a) to (d). The display section 282 of the observation unit 271 displaysthe luminances at these points (a) to (d), as is shown in FIG. 45.

[0259] The input device (e.g., keyboard, mouse, track ball, touch pen,or the like) is connected to the reference luminance setting means 284,too. As the input device is operated, the means 284 sets a referenceluminance value Ls for each measuring point. When the luminances at allpoints (a) to (d) exceed the reference luminance values, the observationunit 271 outputs a therapy stop signal to the therapeutic energygenerator 268, which stops generating therapeutic energy.

[0260] The therapeutic system 261, i.e., the twenty-fifth embodiment ofthe invention, will be described with reference to the flow chart ofFIG. 47.

[0261] In Step S71, the MRI apparatus 262 is operated, generating an MRIimage before the therapeutic probe 270 is operated to perform therapy.Then, in Step S72, the MRI controller 265 transfers an image signal tothe observation unit 271. In Step S73, the display section 282 of theobservation unit 271 displays the MR image generated by the MRIapparatus 262.

[0262] Thereafter, in Step S74, a doctor operates the input device(e.g., keyboard, mouse, track ball, touch pen, or the like) whileobserving the MR image displayed on the screen of the display section282. The measuring-points setting section 283 of the observation unit271 sets four measuring points (a) to (d) in the MR image, around theimage Hj of the affected region as is illustrated in FIG. 44. In StepS75, the doctor operates the input device again, while observing the MRIimage displayed on the screen of the display section 282. Therefore, thereference luminance setting means 284 sets a reference luminance valueLs for each measuring point.

[0263] Therapy is then started in Step S76. More specifically, thetherapeutic energy generator 268 supplies a therapy start signal to theobservation unit 271 in Step S77. In Step 78, the MRI apparatus 262generates an MRI image. In Step S79, the MRI controller 265 transfers animage signal to the observation unit 271.

[0264] In Step S80, the luminance at each measuring point is measuredand displayed as shown in FIG. 45. In Step S81, it is determined whetherall luminances at the points (a) to (d) exceed the reference luminancevalues Ls, respectively. If NO, the operation returns to Step 78. IfYES, the therapy is terminated in Step S82. In Step S83, the indicatormeans 285 of the observation unit 271 is operated, indicating that thetherapy has been terminated.

[0265] As the therapy proceeds, the colors of the parts of the MR image,which are at the measuring points (a) to (d), change from white to blackor vice versa, for example, depending on the parameters which have beenset. Hence, the colors of these parts of the MR image change to eitherblack or white when the luminances at all measuring points (a) to (d)exceed the reference luminance values Ls, respectively.

[0266] In the twenty-fifth embodiment, the input device (e.g., keyboard,mouse, track ball, touch pen, or the like) is operated, setting fourmeasuring points (a) to (d) in the MR image, around the image Hj of theaffected region as is illustrated in FIG. 44. The input device isoperated again, setting four reference luminance values Ls for themeasuring points (a) to (d), respectively. When the luminances at allmeasuring points exceed the reference values Ls, respectively, thetherapeutic energy generator 268 stops applying therapeutic energy tothe affected region. Thus, the therapy is automatically terminated whenthe luminances at all measuring points exceed the reference values Ls.The influence of the therapy energy on the living tissues in the patientis therefore minimized. When the luminances at all measuring pointsexceed the reference values Ls, it is known that the therapy has beenthoroughly achieved on the entire affected region, This is because thefour measuring points (a) to (d) surround the image Hj of the affectedregion.

[0267] With the therapeutic system according to the twenty-fifthembodiment, it is possible to perform the MR imaging (i.e., providing anMRI tomogram by means of the MRI apparatus 262) and the therapy (i.e.,applying therapy energy by means of the probe 270), either at the sametime or alternately.

[0268] A therapeutic system according to the twenty-sixth embodiment ofthis invention will be described, with reference to the flow chart ofFIG. 48. The twenty-sixth embodiment differs from the twenty-fifthembodiment (FIGS. 43 to 47) only in the steps of operation which arecarried out after the completion of therapy.

[0269] In the twenty-sixth embodiment, Steps S71 to S83 are carried outin the same order as in the twenty-fifth embodiment (see the flow chartof FIG. 47). After the indicator means 285 informs, in Step S83, thatthe therapy should be terminated, the observation unit 271 supplies atherapy end signal to the therapeutic energy generator 268 in Step S84.In Step S85, the generator 268 stops applying therapeutic energy to theaffected region, whereby the therapy is terminated. More precisely, thetherapeutic probe 270 stops applying the energy in response to thetherapy end signal. Alternatively, the therapy energy applied from theprobe 270 may be decreased in response to the therapy end signal,thereby to terminate the therapy automatically.

[0270] In the twenty-sixth embodiment, the probe 270 stops applying thetherapy energy or the therapy energy applied from the probe 270 isdecreased when the affected region is thoroughly treated. In otherwords, the therapy is automatically terminated the moment the affectedregion is completely treated. The influence of the therapy energy on theliving tissues in the patient is therefore minimized.

[0271] A therapeutic system according to the twenty-seventh embodimentof the invention will be described, with reference to FIGS. 49 and 50.This embodiment differs from the twenty-fifth embodiment (FIGS. 43 to47) in that a luminance ratio setting means 291 is provided in theobservation unit 271. The therapeutic system 261 is operated, as will beexplained with reference to the flow chart of FIG. 50.

[0272] As can be understood from FIGS. 47 and 50, Steps S71 to S75 areperformed in the same order as in the twenty-fifth embodiment. After thedoctor operates the input device (e.g., keyboard, mouse, track ball,touch pen, or the like), thus setting four reference luminance values Lsfor the measuring points (a) to (d), respectively, in Step S75, theoperation goes to Step S91.

[0273] In Step S91, the doctor operates the input device again, wherebythe luminance ratio setting means 291 sets four luminance ratios for themeasuring points (a) to (d), respectively. Each of the luminance ratios,thus set, is the ratio of a maximum luminance to the reference luminanceLs set for that measuring point. The maximum luminance is a valueexperimentally obtained, which that part of the MR image has at themeasuring point when the affected region is completely treated.

[0274] Thereafter, in Step S76, the therapy is started as in thetwenty-fifth embodiment. Then, Steps 77 to S80 are carried out in thesame order as in the twenty-fifth embodiment. After the luminances atthe measuring points (a) to (d) have been measured and displayed in StepS80, the operation goes to Step S92.

[0275] In Step S92, it is determined whether the ratio of the luminanceat each measuring point to the reference luminance Ls set for the pointhas exceeded the luminance ratio set for the point in Step S91. If NO,the operation returns to Step S78. If YES in Step S92, the therapy isterminated in Step S82. In Step S83, the indicator means 285 of theobservation unit 271 is operated, indicating that the therapy has beenterminated.

[0276] The twenty-seventh embodiment is advantageous in that theaffected region would not be treated excessively at all. This is becausethe therapy on the affected region is automatically terminated when itis determined that the ratio of the luminance at each measuring point tothe reference luminance Ls set for the point has exceeded the luminanceratio set for the point.

[0277] In the twenty-seventh embodiment, a therapy end signal may besupplied to the therapeutic energy generator 268 as in the twenty-sixthembodiment (FIG. 48). In response to the therapy end signal, thegenerator 268 stops applying therapeutic energy to the affected region.Alternatively, the therapy energy applied from the probe 270 may bedecreased in response to the therapy end signal.

[0278] A therapeutic system according to the twenty-eighth embodiment ofthe invention will be described, with reference to FIG. 51. Thetwenty-eighth embodiment differs from the twenty-fifth embodiment (FIGS.43 to 47) in the operation prior to the therapy accomplished by the useof the therapeutic probe 270.

[0279] As can be understood from FIGS. 47 and 51, Steps S71 to S73 areperformed in the same order as in the twenty-fifth embodiment. After thedisplay section 282 of the observation unit 271 displays the MR image inStep S73, the operation goes to Step S101. In Step S101, the MRI imagedisplayed by the display section 282 is analyzed, thereby identifyingthe image Hj of the affected region and setting four measuring points(a) to (d) around the image Hj of the affected region. Then, in StepS102, the measuring-points setting section 283 sets additional measuringpoints around the image Hj, and the positions of the points (a) to (d)automatically set are adjusted. Thereafter, the operation goes to StepS75. Steps S75 to S83 are performed in the same order as in thetwenty-fifth embodiment.

[0280] The twenty-eighth embodiment is advantageous in that the MRIapparatus 261 and the therapeutic probe 270 can be operated easily atthe same time. This is because the image Hj of the affected region isautomatically identified by analyzing the MR image displayed by thedisplay section 282, and the measuring points (a) to (d) are then setaround the image Hj of the affected region.

[0281] A therapeutic system according to the twenty-ninth embodiment ofthe invention will be described, with reference to FIG. 52. Thetwenty-ninth embodiment differs from the twenty-seventh embodiment(FIGS. 49 to 50) in the operation after the therapy accomplished by theuse of the therapeutic probe 270.

[0282] As can be understood from FIGS. 50 and 52, Steps S71 to S92 areperformed in the same order as in the twenty-seventh embodiment. If itis determined in Step S92 that the ratio of the luminance at eachmeasuring point to the reference luminance Ls set for the point hasexceeded the luminance ratio set for the point, the operation goes toStep S111.

[0283] In Step S111, the indicator means 285 of the observation unit 271is operated, indicating that the therapy should be terminated. Theoperation then goes to Step S81 that is identical to Step S81 shown inthe flow chart of FIG. 47 that explains the operation of thetwenty-fifth embodiment (FIGS. 43 to 47). In Step S81, it is determinedwhether all luminances at the points (a) to (d) exceed the referenceluminance values Ls, respectively. If NO, the operation returns to Step78. If YES, the therapy is terminated in Step S82.

[0284] Then, in Step S112, the observation unit 271 supplies a therapyend signal to the therapeutic energy generator 268. In Step S113, thegenerator 268 stops applying therapeutic energy to the affected region,whereby the therapy is terminated. More precisely, the therapeutic probe270 stops applying the energy in response to the therapy end signal.Alternatively, the therapy energy applied from the probe 270 may bedecreased in response to the therapy end signal, thereby to terminatethe therapy automatically.

[0285] The twenty-ninth embodiment described above is advantageous inthat the therapy is automatically terminated in safety. This is becausethe indicator means 285 is operated, indicating that the therapy shouldbe terminated, when it is determined that the ratio of the luminance ateach measuring point to the reference luminance Ls set for the point hasexceeded the luminance ratio set for the point. Then, the therapeuticenergy generator 268 stops applying therapeutic energy to the affectedregion.

[0286] FIGS. 53 to 55 show a therapeutic system, which is the thirtiethembodiment of the present invention. The thirtieth embodiment differsfrom the twenty-fifth embodiment (FIGS. 43 to 47) in the followingrespects.

[0287] As shown in FIG. 54, the observation unit 271 has an additionalcomponent, i.e., a reference point setting means 301. The referencepoint setting means 301 is designed to set a reference point R in the MRimage generated by the MRI apparatus 262, while the measuring-pointssetting section 283 sets four measuring points (a) to (d). Furthermore,the reference luminance values Ls are not set for the four measuringpoints (a) to (d) as in the twenty-fifth embodiment. Instead, aluminance ratio setting means 302 sets ratio of each reference luminancevalue Ls to the reference luminance value for the reference point R.

[0288] As shown in FIG. 53, the reference point R is set in the MR imageHk of a region that surrounds the image Hj of the affected region andthat is supposed to be not influenced by the therapeutic energy appliedfrom the probe 270. The therapeutic system is operated as will beexplained below, with reference to the flow chart of FIG. 55.

[0289] As can be understood from FIGS. 47 and 55, Steps S71 to S74 areperformed in the same order as in the twenty-fifth embodiment (FIGS. 43to 47). After the four measuring points (a) to (d) have been set aroundthe image Hj of the affected region as shown in FIG. 53, the operationgoes to Step S121. In Step S121, the input device (e.g., keyboard,mouse, track ball, touch pen, or the like) is operated, whereby thereference point setting means 301 sets a reference point R in the imageHk as is illustrated in FIG. 53. In Step S122, the input device (notshown) is operated again, whereby the luminance ratio setting means 302sets the ratios of the four reference luminance values Ls set for themeasuring points (a) to (d) to the reference luminance value set for thereference point R.

[0290] Thereafter, in Step S76, the therapy is started in the same wayas in the twenty-fifth embodiment. Steps S76 to S80 are carried out inthe same order as in the twenty-fifth embodiment. After the luminancesat the four measuring points (a) to (d) are measured and displayed inStep S80, the operation goes to Step S123.

[0291] In Step S123, it is determined whether all four luminance ratiosset by the luminance ratio setting means 302 have exceeded a prescribedvalue or not. If NO, the operation returns to Step S78. If YES, theoperation goes to Step S82, in which the therapy is terminated. In StepS83, the indicator means 285 informs that the therapy has beenterminated.

[0292] The thirtieth embodiment is advantageous in that the terminationof therapy is reliably recognized. This is because The reference pointsetting means 301 sets a reference point R in the MR image generated bythe MRI apparatus 262, and the luminance ratio setting means 302 setsthe ratios of the four reference luminance values Ls to the referenceluminance value set for the reference point R. Thus, the influence ofindividual differences or MRI parameters on the luminance at eachmeasuring point can be compensated for.

[0293]FIGS. 56 and 57 show a therapeutic system according to thethirty-first embodiment of the present invention. This embodimentdiffers from the thirtieth embodiment in the following respects.

[0294] As shown in FIG. 56, the observation unit 271 incorporates amemory means 311, instead of the reference point setting means 301. Thememory means 311 is provided for storing the initial values of theluminances at the measuring points (a) to (d).

[0295] The operation of the thirty-first embodiment will be explained,with reference to the flow chart of FIG. 57.

[0296] As can be understood from FIGS. 47 and 57, Steps S71 to S75 areperformed in the same order as in the twenty-fifth embodiment (FIGS. 43to 47). After the reference luminance value Ls for the four measuringpoints (a) to (d) have been set in Step S75, the operation goes to StepS131. In Step 131, the initial luminance values Ls set for the points(a) to (d) are stored into the memory means 311.

[0297] Then, the therapy is started in Steps S76 in the same way as inthe thirtieth embodiment. Steps S77 to S80 are carried out in the sameorder as in the thirtieth embodiment. After the luminances at the fourmeasuring points (a) to (d) are measured and displayed in Step S80, theoperation goes to Step S132. In Step S132, it is determined whether allfour ratios of the luminances at the measuring points (a) to (d) to theinitial values stored in the memory means 311 have exceeded a prescribedvalue or not. If YES, the operation goes to Step S82, in which thetherapy is terminated. In this case, the indicator means 285 informs, inStep S83, that the therapy has been terminated. If NO in Step S132, theoperation returns to Step S78, whereby Steps S78, S79, S80 and S132 arerepeated.

[0298] In the thirty-first embodiment described above, the memory means311 stores the initial luminance values Ls set for the points (a) to(d). The therapy is terminated when the ratios of the luminances at thepoints (a) to (d) set around the image Hj of the affected region, to theinitial values stored in the memory means 311 have exceeded a prescribedvalue. Therefore, the thirty-first embodiment attains the same advantageas the thirtieth embodiment. In addition, the thirty-first embodimentcan be used to perform therapy on an organ so small that the referencepoint R can hardly set in an MR image generated by the MRI apparatus262.

[0299]FIGS. 58 and 59 show a therapeutic system according to thethirty-second embodiment of the present invention. This embodimentdiffers from the thirty-first embodiment in the following respects.

[0300] As shown in FIG. 58, the observation unit 271 incorporates aluminance-change rate setting means 321 and a luminance-change ratecalculating means 322, instead of the luminance rate setting means 302.Whether or not the therapy has should be terminated is determined inaccordance with the luminance-change rates at the measuring points (a)to (d). The decision is not made in accordance with the luminancesmeasured at the points (a) to (d) as in the thirty-first embodiment.

[0301] The operation of the thirty-second embodiment will be explained,with reference to the flow chart of FIG. 59. Steps S71 to S74 arecarried out in the same order as in the twenty-fifth embodiment (FIGS.45 to 47). After the four measuring points (a) to (d) have been setaround the image Hj of the affected region, the operation goes to StepS141. In Step S141, the input device (e.g., keyboard, mouse, track ball,touch pen, or the like) is operated, whereby the luminance-change ratesetting means 321 sets four luminance-change rates for the measuringpoints (a) to (d), respectively.

[0302] Thereafter, in Step S76, the therapy is started in the same wayas in the twenty-fifth embodiment. Steps S77 to S80 are then performedin the same order as in the twenty-fifth embodiment. After theluminances at the four measuring points (a) to (d) are measured anddisplayed in Step S80, the operation goes to Step S142. In Step S142,the luminances at the points (a) to (d) are stored into the memory means311. In Step S143, the luminance-change rate calculating means 322calculates the luminance-change rates at the points (a) to (d). In StepS144, it is determined whether all luminance-change rates calculated aresmaller than the four luminance-change rates that the luminance-changerate setting means 321 has set for the measuring points (a) to (d). IfNO, the operation returns to Step S78. In this case, Steps S78 to S80and Steps S141 to S143 are repeated. If YES in Step S144, the operationgoes to Step S82, in which the therapy is terminated. In Step S83, theindicator means 285 informs that the therapy has been terminated.

[0303] In the thirty-second embodiment described above, whether thetherapy should be terminated is determined in accordance with theluminance-change rates at the measuring points (a) to (d), not inaccordance with the luminances measured at the points (a) to (d). Inthis regard, it should be noted that the luminance at any point in theimage Hj of the affected region will not change once the affected regionhas been heated, becoming completely void of water. This is why theluminance-change rates at the measuring points (a) to (d) are monitoredin the thirty-second embodiment. The thirty-second embodiment isadvantageous in that it can be reliably determined whether the livingtissues present in the affected region have perished.

[0304] FIGS. 60 to 63 show a therapeutic system, which is thethirty-third embodiment of this invention. The present embodimentdiffers from the thirty-second embodiment (FIGS. 58 and 59) in thefollowing respects.

[0305] As shown in FIG. 60, the observation unit 271 incorporates areference line setting means 331, instead of the measuring-pointssetting section 283. The reference-line setting means 331 is designed toset a reference line Lb in the MR image generated by the MRI apparatus262, as illustrated in FIG. 62. The reference line Lb extends in a givendirection from the energy-emission center O of the therapeutic probe270, from which therapeutic energy is applied to the affected region Hj.A plurality of measuring points are set on the reference line Lb andspaced at regular intervals. Luminaces at these points are measured.

[0306] The operation of the thirty-third embodiment will be describedwith reference to the flow chart of FIG. 61.

[0307] As shown in FIG. 61, Steps S71 to S73 are carried out in the sameorder as in the twenty-fifth embodiment (FIGS. 45 to 47). After thedisplay section 282 of the observation unit 271 displays the MR image inStep S73, the operation goes to Step S151. In Step S151, the inputdevice (e.g., keyboard, mouse, track ball, touch pen, or the like) isoperated, whereby the reference-line setting means 331 sets a referenceline Lb in the RM image generated by the MRI apparatus 262. In StepS152, the input device (not shown) is operated again, whereby theluminance-change rate setting means 321 sets a luminance-change rate forthe reference line Lb.

[0308] Then, in Step S76, the therapy is started in the same way as inthe twenty-fifth embodiment. Steps S77 to S79 are then performed in thesame order as in the twenty-fifth embodiment. After the MRI controller265 transfers an image signal to the observation unit 271 in Step S79,the operation goes to Step S153.

[0309] In Step S153, the luminances at the measuring points on thereference line Lb are measured and displayed. Then, in Step S154, theluminaces measured at these measuring points are stored into the memorymeans 311. In Step S155, the luminance-change rate calculating means 322calculates the luminance-change rates at the measuring points.

[0310] Next, in Step S156, it is determined whether all luminance-changerates calculated for all measuring points are smaller than the fourluminance-change rates that the means 321 has set for the measuringpoints. If NO, the operation returns to Step S78. If YES in Step S156,the operation goes to Step S82, in which the therapy is terminated. InStep S83, the indicator means 285 informs that the therapy has beenterminated.

[0311]FIG. 63 shows how the luminance changes along the reference lineLb set in the MR image generated by the MRI apparatus 262, during thetherapy accomplished by the use of the therapeutic probe 270. In FIG.63, the distance from the therapeutic probe 270 is plotted on the Xaxis, and the luminance on the Y axis. While the probe 270 applies thetherapeutic energy, the luminance distribution changes with time as isindicated by curves P1 to P5. As can be understood from FIG. 63, theluminance stops increasing once it reaches a specific value. The displaysection 282 of the observation unit 271 displays the curves P1 to P5.Alternatively, the display section 282 may display the luminance-changerates at some measuring points on the reference line Lb, in the form ofsuch a bar graph as is shown in FIG. 39.

[0312] As mentioned above, a reference line Lb is set which extends in agiven direction from the energy-emission center O of the therapeuticprobe 270 applying therapeutic energy to the affected region Hj, andluminance-change rates at some measuring points automatically set on thereference line Lb are measured. On the basis of the luminance-changerates measured it is determined whether or not the therapy should beterminated.

[0313] As the therapeutic probe 270 applies the therapeutic energy tothe affected region Hj, the temperature in the region Hj graduallyrises. Once the region Hj has become completely void of water, there areno longer changes in the water content in the affected region Hj. Inother words, the luminance at any measuring point no longer change,however much energy is applied to the affected region Hj. Thus, it isreliably determined that the therapy should be terminated, becauseluminance-change rates are measured at some measuring points which havebeen automatically set on the reference line Lb extending from theenergy-emission center O of the therapeutic probe 270.

[0314] FIGS. 64 to 66 show a therapeutic system according to thethirty-fourth embodiment of the present invention. The thirty-fourthembodiment differs from the thirty-third embodiment (FIGS. 60 to 63) inthe following respects.

[0315] As shown in FIG. 64, the observation unit 271 incorporates areference point setting means 341 and a reference luminance settingmeans 284, instead of the reference line setting means 331 and theluminance-change rate setting means 321.

[0316] The operation of the therapeutic system, which is thethirty-fourth embodiment, will be explained with reference to the flowchart of FIG. 65.

[0317] Steps S71 to S73 are carried out in the same order as in thetwenty-fifth embodiment (FIGS. 45 to 47) and as is illustrated in theflow chart of FIG. 47. After the display section 282 of the observationunit 271 displays the MR image in Step S73, the operation goes to StepS161. In Step S161, the input device (e.g., keyboard, mouse, track ball,touch pen, or the like) is operated, whereby the reference point settingmeans 341 sets a reference point X1 in the image of the affected region.

[0318] Thereafter, in Step S76, the therapy is started as in thetwenty-fifth embodiment. Steps S77 to S80 are then performed in the sameorder as in the twenty-fifth embodiment. In Step S80, the luminance atthe reference point X1 is measured. In Step S163, it is determinedwhether or not the luminance at the reference point X1 has exceeded thereference level V1 set by the luminance setting means 284. If NO, theoperation returns to Step S78. If YES, the operation goes to Step S82,the operation goes to Step S83. In Step S83, the indicator means 285 ofthe observation unit 271 informs that the therapy has been terminated.

[0319] As the therapeutic probe 270 applies the therapeutic energy tothe affected region Hj (i.e., living tissues), heat propagates likeripples, from the energy-emission center O in the RMI tomogram of theaffected region Hj. Therefore, it can be confirmed how much the affectedregion Hj has been treated, by comparing the reference level V1 set bythe luminance setting means 284 with the luminance at the referencepoint X1 which is at a certain distance from the energy-emission centerO.

[0320] Moreover, the display section 282 of the observation unit 271displays the relation between the luminance measured at the point set bythe reference point setting means 341 and the distance between thispoint and the energy-emission center O, as is illustrated in FIG. 66. Itis therefore easy for a doctor to visually understand how much theaffected region Hj has been treated. If the relation is represented by acurve P1, indicating that the luminance at distance X1 is higher thanthe reference level V1, the doctor recognizes that the therapy can becontinued. On the other hand, if the relation is represented by a curveP2, indicating that the luminance at distance X1 is lower than thereference level V1, the doctor understands that the therapy should beterminated.

[0321] Thus, the thirty-fourth embodiment is advantageous in that thedoctor can visually understand how much the affected region Hj has beentreated, merely by looking at the luminance-distance curve displayed bythe display section 282 of the observation unit 271.

[0322] FIGS. 67 to 69 show a therapeutic system according to thethirty-fifth embodiment of the invention. The thirty-fifth embodimentdiffers from the twenty-fifth embodiment (FIGS. 45 to 47) in thefollowing respects.

[0323] As shown in FIG. 67, an ultrasonic imaging apparatus 215 isprovided, instead of the MRI apparatus 262, for detecting the positionof the therapeutic probe 270. The ultrasonic imaging apparatus 215 is,for example, of the same type as the one used in the twenty-secondembodiment (FIG. 40).

[0324] As shown in FIG. 68, the ultrasonic imaging apparatus 215comprises an ultrasonic imaging section 351 and an image signal outputsection 352. A diagnostic ultrasonic probe 212 is connected to the inputof the ultrasonic imaging section 351. The image signal input unit 281of the observation unit 271 is connected to the image signal outputsection 352 by the signal cable 353.

[0325] The therapeutic system shown in FIG. 67 is operated as will bedescribed below, with reference to the flow chart of FIG. 69.

[0326] First, the diagnostic ultrasonic probe 212 generates anultrasonic image in Step S171, prior to the therapy performed by meansof the therapeutic probe 270. In Step S172, the image signalrepresenting the ultrasonic image is transferred from the ultrasonicimaging apparatus 215 to the observation unit 271. In Step S173, thedisplay section 282 of the observation unit 271 displays the ultrasonicimage the ultrasonic probe 212 has generated.

[0327] Thereafter, in Step S174, the doctor operates the input device(e.g., keyboard, mouse, track ball, touch pen, or the like), whileobserving the ultrasonic image displayed on the screen of the displaysection 282 of the observation unit 271. As a result, themeasuring-points setting section 283 of the observation unit 271 setsfour measuring points (a) to (d) in the ultrasonic image, around theimage Hj of the affected region as is illustrated in FIG. 44. In StepS175, the doctor operates the input device again, while observing theultrasonic image, setting four reference luminance values Ls for themeasuring points (a) to (d), respectively.

[0328] In Step S176, the therapy is started. More precisely, thetherapeutic energy generator 268 supplies a therapy start signal to theobservation unit 271 in Step S177. In Step S178, the ultrasonic imagethe ultrasonic probe 212 applies ultrasonic waves, whereby theultrasonic imaging apparatus 215 transfers an image signal to theobservation unit 271.

[0329] In Step S180, the luminances at the four measuring points (a) to(d) are monitored. In Step S181, it is determined whether the luminanceshave exceeded the reference values Ls, respectively. If NO, theoperation returns to Step S178. If YES, the operation goes to Step S182,in which the therapy is terminated. Then, in Step S183, the indicatormeans 285 of the observation unit 271 informs that the therapy has beenterminated.

[0330] In the thirty-fifth embodiment, the therapy is automaticallyterminated in the same way as in the twenty-fifth embodiment. Theinfluence of the therapy energy on the living tissues in the patient istherefore minimized. Further, the affected region can be reliablytreated in its entirety, because the therapy is terminated when theluminances exceed the reference luminances Ls at the four measuringpoints (a) to (d) set around the image Hj of the affected region.

[0331] In the thirty-fifth embodiment, the ultrasonic imaging apparatus215 of the same type as the one incorporated in the twenty-secondembodiment (FIG. 40) is used as an observation means for detecting theposition of the therapeutic applicator. The ultrasonic imaging apparatus215 can be used in the other embodiments, as well.

[0332] Utilizing a component or components of any other embodiment canmodify each of the embodiments described above. For instance, in thetherapeutic system according to the thirty-fifth embodiment (FIGS. 67 to69), that incorporates the ultrasonic imaging apparatus 215, thetherapeutic energy generator 268 may be automatically turn on and off asin the twenty-sixth embodiment (FIG. 48).

[0333] The present invention is not limited to the embodiments describedabove. Various changes and modifications can be made, without departingthe scope of the present invention.

[0334] Additional advantages and modifications will readily occur tothose skilled in the art. Therefore, the invention in its broaderaspects is not limited to the specific details and representativeembodiments shown and described herein. Accordingly, variousmodifications may be made without departing from the spirit or scope ofthe general inventive concept as defined by the appended claims andtheir equivalents.

1. A therapeutic system comprising: a therapeutic applicator adapted tobe inserted into a body cavity, for applying therapeutic energy to treatliving tissues present in the body cavity; observation means forindicating a position which the therapeutic applicator takes in the bodycavity; and control means for controlling the therapeutic energy appliedfrom the therapeutic applicator to the living tissues, on the basis ofdata representing the position which the therapeutic applicator takes inthe body cavity.
 2. A therapeutic system according to claim 1, whereinthe observation means comprises image diagnostic apparatus capable ofindicating the position of the therapeutic applicator, and the controlmeans controls the therapeutic energy in accordance with a signalsupplied from the image diagnostic apparatus.
 3. A therapeutic systemcomprising: an image diagnostic apparatus; a therapeutic apparatus forapplying therapeutic energy to an affected region; and a controlapparatus for supplying signals between the image diagnostic apparatusand the therapeutic apparatus.
 4. A therapeutic system according toclaim 3, wherein the control apparatus is designed to decrease an outputof the therapeutic apparatus or inhibit the therapeutic apparatus fromapplying therapeutic energy, while the affected region is diagnosed bythe use of the image diagnostic apparatus.
 5. A therapeutic systemaccording to claim 4, wherein the control apparatus is designed to causethe image diagnostic apparatus to display an image of the affectedregion for diagnostic purpose, after decreasing the output of thetherapeutic apparatus or inhibiting the therapeutic apparatus fromapplying therapeutic energy.
 6. A therapeutic system according to claim3, wherein the control apparatus is designed to determine a rate atwhich the affected region is being treated, from changes in an imagedisplayed by the image diagnostic apparatus, and to change variousvalues set in the therapeutic apparatus in accordance with the rate thusdetermined.
 7. A therapeutic system according to claim 3, wherein saidimage diagnostic apparatus comprises an MRI apparatus, and the controlapparatus is designed to supply an MRI start signal and an MRI stopsignal to the MRI apparatus.
 8. A therapeutic system according to claim7, wherein the control apparatus is designed to supply MRI parameters tothe MRI apparatus.
 9. A therapeutic system according to claim 7, whereinthe control apparatus is designed to supply an MRI signal from the MRIapparatus.
 10. A therapeutic system according to claim 3, wherein thecontrol apparatus is designed to supply an output start signal, anoutput stop signal and a output-level setting signal to the therapeuticapparatus.
 11. A therapeutic system according to claim 3, wherein saidtherapeutic apparatus has a therapeutic section adapted to contactliving tissues, and the control apparatus is designed to supply atissue-separating current to the living tissues to remove the tissuesfrom the therapeutic section when the therapeutic apparatus stopsapplying the therapeutic energy.
 12. A therapeutic system according toclaim 3, wherein the image diagnostic apparatus comprises an MRIapparatus, the therapeutic apparatus has a therapeutic section adaptedto contact living tissues, and the control apparatus is designed todecrease an output of the therapeutic apparatus or inhibit thetherapeutic apparatus from applying therapeutic energy, while theaffected region is diagnosed by the use of the image diagnosticapparatus, to cause the image diagnostic apparatus to display an imageof the affected region for diagnostic purpose, after decreasing theoutput of the therapeutic apparatus or inhibiting the therapeuticapparatus from applying therapeutic energy, to determine a rate at whichthe affected region is being treated, from changes in an image displayedby the image diagnostic apparatus, and change various values set in thetherapeutic apparatus in accordance with the rate thus determined, tosupply an MRI start signal and an MRI stop signal to the MRI apparatus,to supply MRI parameters to the MRI apparatus, to supply an MRI signalfrom the MRI apparatus, to supply an output start signal, an output stopsignal and a output-level setting signal to the therapeutic apparatus,and to supply a tissue-separating current to the living tissues toremove the tissues from the therapeutic section when the therapeuticapparatus stops applying the therapeutic energy.
 13. A therapeuticsystem according to claim 12, wherein the therapeutic apparatuscomprises a therapeutic applicator which is compatible with the MRIapparatus.
 14. A therapeutic system comprising: energy generating meansfor generating therapeutic energy; a therapeutic applicator for applyingthe therapeutic energy generated by the energy generating means to treatliving tissues; tomogram generating means for generating a tomogram ofan affected region; an energy supplying path provided between the energygenerating means and the therapeutic applicator; a noise filter providedin the energy supplying path, for removing a frequency component thatinfluences the tomogram generating means, from the therapeutic energygenerated by the energy generating means.
 15. A therapeutic systemaccording to claim 14, wherein the energy generating means is amicrowave generating apparatus
 16. A therapeutic system according toclaim 14, wherein the energy generating means is a high-frequency wavegenerating apparatus.
 17. A therapeutic system according to claim 14,wherein the tomogram generating means is an MRI apparatus.
 18. Atherapeutic system according to claim 14, wherein the tomogramgenerating means is a n ultrasonic imaging apparatus.
 19. An therapeuticsystem according to claim 14, wherein the noise filter is a band-passfilter which transmits waves having a main output frequency of theenergy generating means.
 20. A therapeutic system according to claim 14,wherein the noise filter is a band-cut filter which attenuates waveshaving an input frequency of the tomogram generating means.
 21. Atherapeutic system according to claim 14, wherein the noise filter alow-pass filter or a high-pass filter which transmits waves having afrequency lower than a main output frequency of the energy generatingmeans and higher than an average of the main output frequency of theenergy generating means and an input frequency of the tomogramgenerating means.
 22. A therapeutic system according to claim 14,wherein the tomogram generating means comprises a magnetic shield roomhaving an input section, and the noise filter is provided in the inputsection of the magnetic shield room.
 23. A therapeutic systemcomprising: energy generating means for generating therapeutic energy;therapeutic means comprising a therapeutic electrode or a therapeuticapplicator for applying the therapeutic energy from the energygenerating means to living tissues present in an affected region,thereby to treat the living tissues, said therapeutic means having aplurality of position-indicating markers; an image diagnostic apparatushaving a display means for displaying a tomogram of the affected region;and a control apparatus for detecting positions of the markers in thetomogram displayed by the display means and for controlling the energygenerating means in accordance with the positions of the markers.
 24. Atherapeutic system according to claim 23, wherein the control apparatuscauses the energy generating means to stop generating the therapeuticenergy, when positional relation of the markers changes.
 25. Atherapeutic system according to claim 23, wherein the control apparatuscauses the energy generating means to stop generating the therapeuticenergy, when none of the markers is detected in the tomogram displayedby the display means.
 26. A therapeutic system according to claim 23,wherein the control apparatus causes the energy generating means to stopgenerating the therapeutic energy, when an image signal representing aprescribed one of the markers changes.
 27. A therapeutic systemcomprising: energy generating means for generating therapeutic energy;therapeutic means comprising a therapeutic electrode or a therapeuticapplicator for applying the therapeutic energy from the energygenerating means to living tissues present in an affected region,thereby to treat the living tissues, said therapeutic means having aplurality of position-indicating markers; an image diagnostic apparatushaving a display means for displaying a tomogram of the affected region;drive means for moving the therapeutic means; and a control unit fordetecting the markers in the tomogram displayed by the display means andfor controlling the energy generating means and the drive means inaccordance with the positions of the markers.
 28. A therapeutic systemcomprising: energy generating means for generating therapeutic energy;therapeutic means for applying therapeutic energy from the energygenerating means to living tissues present in an affected region,thereby to treat the living tissues; tomogram generating means forgenerating a tomogram of the affected region; observation unit forsetting measuring points or a reference line in the tomogram generatedby the tomogram generating means and for determining how much the livingtissues have been treated, from image data acquired at the measuringpoints or on the reference line.
 29. A therapeutic system according toclaim 28, wherein the observation unit has means for indicating how muchthe living tissues have been treated.
 30. A therapeutic system accordingto claim 29, wherein the observation unit determines whether therapyshould be terminated.
 31. A therapeutic system according to claim 28,wherein the observation unit inhibits the energy generating means fromgenerating the therapeutic energy or decreases the therapeutic energygenerated by the energy generating means.
 32. A therapeutic systemaccording to claim 31, wherein the observation unit determines whethertherapy should be terminated.
 33. A therapeutic system according toclaim 28, wherein the observation unit has manual setting means forsetting the measuring points or the reference line when manuallyoperated.
 34. A therapeutic system according to claim 28, wherein theobservation unit has automatic setting means for setting the measuringpoints or the reference line on the basis of tomogram data supplied fromthe tomogram generating means.
 35. A therapeutic system according toclaim 28, wherein the observation unit has means which uses, as imagedata values, the absolute values of luminances at the measuring points.36. A therapeutic system according to claim 28, wherein the observationunit has means which sets a reference point in the tomogram and whichuses, as image data values, the relative values of the luminances at thereference point and the measuring points.
 37. A therapeutic systemaccording to claim 28, wherein the observation unit has means whichuses, as image data values, differences between the luminances measuredat the measuring points before the therapeutic energy is applied and theluminances measured at the measuring points when the therapeutic energyis applied.
 38. A therapeutic system according to claim 28, wherein theobservation unit has means which uses, as image data values, theluminance-change rates measured at the measuring points.
 39. Atherapeutic system according to claim 28, wherein the observation unitis designed to determine that the image data values at all measuringpoints have reached threshold values, respectively.
 40. A therapeuticsystem according to claim 28, wherein the observation unit is designedto set a plurality of measuring points in the tomogram and to determinethat the image data values at all measuring points have reachedthreshold values set for the measuring points, respectively.
 41. Atherapeutic system according to claim 28, wherein the observation unitis designed to set a first group of measuring points and a second groupof measuring points in the tomogram, to determine whether the image datavalues at the measuring points have reached threshold values,respectively, to determine and indicate that the image data values atthe measuring points of the first group have reached the thresholdvalues, and to inhibit the energy generating means from generating thetherapeutic energy or decreases the therapeutic energy generated by theenergy generating means, when determining that the image data values atthe measuring points of the second group have reached the thresholdvalues.
 42. A therapeutic system according to claim 28, wherein theobservation unit is designed to use, as image data values, theluminance-change rates measured at the measuring points.
 43. Atherapeutic system according to claim 28, wherein the observation unitis designed to set the measuring points by setting a reference line anddistances from the reference line.
 44. A therapeutic system comprising:a therapeutic applicator adapted to be inserted into a body cavity, forapplying therapeutic energy to treat living tissues present in the bodycavity, said therapeutic applicator comprising a rod-shaped body and aconductor provided in the rod-shaped body and made of material havingmagnetic susceptibility of −10⁻³ to +10⁻³; and observation means forindicating a position which the therapeutic applicator takes in the bodycavity.
 45. A therapeutic system according to claim 44, wherein thetherapeutic applicator has an MR marker made of material which hasmagnetic susceptibility having an absolute value equal to or greaterthan magnetic susceptibility of the material of the rod-shaped body. 46.A therapeutic system according to claim 45, wherein the therapeuticapplicator has a plurality of MR markers made of material which hasmagnetic susceptibility having an absolute value equal to or greaterthan magnetic susceptibility of the material of the rod-shaped body. 47.A therapeutic system according to claim 45, wherein the therapeuticapplicator has an energy-applying section, and the MR marker is arrangedon a distal portion of the energy-applying section.
 48. A therapeuticsystem according to claim 45, wherein the therapeutic applicator has anenergy-applying section, and the MR marker is arranged on a proximalportion of the energy-applying section.
 49. A therapeutic systemaccording to claim 46, wherein the therapeutic applicator has anenergy-applying section, and the MR markers are arranged on a distalportion and proximal portion of the energy-applying section,respectively.
 50. A therapeutic system according to claim 45, whereinthe therapeutic applicator has an energy-applying section, and the MRmarker is located at a distance of 10 mm or more from theenergy-applying section in an axial direction thereof.
 51. A method ofcontrolling a therapeutic system comprising a therapeutic applicatoradapted to be inserted into a body cavity, for applying therapeuticenergy to treat living tissues present in the body cavity, andobservation means for indicating a position which the therapeuticapplicator takes in the body cavity, said method comprising the stepsof: generating an image of living tissues by the use of the observationmeans; determining a position which the therapeutic applicator takes inthe body cavity, from the image generated by the use of the observationmeans; and controlling the therapeutic energy applied from thetherapeutic applicator to the living tissues, on the basis of datarepresenting the position which the therapeutic applicator determined.